diff --git a/tools/buildgen/_utils.py b/tools/buildgen/_utils.py
index b9f39f5d810..c3dfb8d5c8a 100644
--- a/tools/buildgen/_utils.py
+++ b/tools/buildgen/_utils.py
@@ -45,7 +45,7 @@ def to_bunch(var: Any) -> Any:
         return [to_bunch(i) for i in var]
     if isinstance(var, dict):
         ret = {}
-        for k, v in var.items():
+        for k, v in list(var.items()):
             if isinstance(v, (list, dict)):
                 v = to_bunch(v)
             ret[k] = v
@@ -57,7 +57,7 @@ def to_bunch(var: Any) -> Any:
 def merge_json(dst: Union[Mapping, List], add: Union[Mapping, List]) -> None:
     """Merges JSON objects recursively."""
     if isinstance(dst, dict) and isinstance(add, dict):
-        for k, v in add.items():
+        for k, v in list(add.items()):
             if k in dst:
                 if k.startswith('#'):
                     continue
diff --git a/tools/buildgen/extract_metadata_from_bazel_xml.py b/tools/buildgen/extract_metadata_from_bazel_xml.py
index 4df9212905e..02abc160982 100755
--- a/tools/buildgen/extract_metadata_from_bazel_xml.py
+++ b/tools/buildgen/extract_metadata_from_bazel_xml.py
@@ -286,12 +286,11 @@ def _compute_transitive_metadata(
 
     # Calculate transitive public deps (needed for collapsing sources)
     transitive_public_deps = set(
-        filter(lambda x: x in bazel_label_to_dep_name, transitive_deps))
+        [x for x in transitive_deps if x in bazel_label_to_dep_name])
 
     # Remove intermediate targets that our public dependencies already depend
     # on. This is the step that further shorten the deps list.
-    collapsed_deps = set(filter(lambda x: x not in exclude_deps,
-                                collapsed_deps))
+    collapsed_deps = set([x for x in collapsed_deps if x not in exclude_deps])
 
     # Compute the final source files and headers for this build target whose
     # name is `rule_name` (input argument of this function).
@@ -361,7 +360,7 @@ def _populate_transitive_metadata(bazel_rules: Any,
 def update_test_metadata_with_transitive_metadata(
         all_extra_metadata: BuildDict, bazel_rules: BuildDict) -> None:
     """Patches test build metadata with transitive metadata."""
-    for lib_name, lib_dict in all_extra_metadata.items():
+    for lib_name, lib_dict in list(all_extra_metadata.items()):
         # Skip if it isn't not an test
         if lib_dict.get('build') != 'test' or lib_dict.get('_TYPE') != 'target':
             continue
@@ -409,7 +408,7 @@ def _generate_build_metadata(build_extra_metadata: BuildDict,
             result[to_name] = lib_dict
 
             # dep names need to be updated as well
-            for lib_dict_to_update in result.values():
+            for lib_dict_to_update in list(result.values()):
                 lib_dict_to_update['deps'] = list([
                     to_name if dep == lib_name else dep
                     for dep in lib_dict_to_update['deps']
@@ -439,15 +438,21 @@ def _convert_to_build_yaml_like(lib_dict: BuildMetadata) -> BuildYaml:
 
     # get rid of temporary private fields prefixed with "_" and some other useless fields
     for lib in lib_list:
-        for field_to_remove in [k for k in lib.keys() if k.startswith('_')]:
+        for field_to_remove in [
+                k for k in list(lib.keys()) if k.startswith('_')
+        ]:
             lib.pop(field_to_remove, None)
     for target in target_list:
-        for field_to_remove in [k for k in target.keys() if k.startswith('_')]:
+        for field_to_remove in [
+                k for k in list(target.keys()) if k.startswith('_')
+        ]:
             target.pop(field_to_remove, None)
         target.pop('public_headers',
                    None)  # public headers make no sense for targets
     for test in test_list:
-        for field_to_remove in [k for k in test.keys() if k.startswith('_')]:
+        for field_to_remove in [
+                k for k in list(test.keys()) if k.startswith('_')
+        ]:
             test.pop(field_to_remove, None)
         test.pop('public_headers',
                  None)  # public headers make no sense for tests
@@ -464,7 +469,7 @@ def _convert_to_build_yaml_like(lib_dict: BuildMetadata) -> BuildYaml:
 def _extract_cc_tests(bazel_rules: BuildDict) -> List[str]:
     """Gets list of cc_test tests from bazel rules"""
     result = []
-    for bazel_rule in bazel_rules.values():
+    for bazel_rule in list(bazel_rules.values()):
         if bazel_rule['class'] == 'cc_test':
             test_name = bazel_rule['name']
             if test_name.startswith('//'):
@@ -575,7 +580,7 @@ def _generate_build_extra_metadata_for_tests(
         if 'grpc_fuzzer' == bazel_rule['generator_function']:
             # currently we hand-list fuzzers instead of generating them automatically
             # because there's no way to obtain maxlen property from bazel BUILD file.
-            print('skipping fuzzer ' + test)
+            print(('skipping fuzzer ' + test))
             continue
 
         # if any tags that restrict platform compatibility are present,
@@ -619,20 +624,20 @@ def _generate_build_extra_metadata_for_tests(
 
     # detect duplicate test names
     tests_by_simple_name = {}
-    for test_name, test_dict in test_metadata.items():
+    for test_name, test_dict in list(test_metadata.items()):
         simple_test_name = test_dict['_RENAME']
         if not simple_test_name in tests_by_simple_name:
             tests_by_simple_name[simple_test_name] = []
         tests_by_simple_name[simple_test_name].append(test_name)
 
     # choose alternative names for tests with a name collision
-    for collision_list in tests_by_simple_name.values():
+    for collision_list in list(tests_by_simple_name.values()):
         if len(collision_list) > 1:
             for test_name in collision_list:
                 long_name = test_name.replace('/', '_').replace(':', '_')
-                print(
+                print((
                     'short name of "%s" collides with another test, renaming to %s'
-                    % (test_name, long_name))
+                    % (test_name, long_name)))
                 test_metadata[test_name]['_RENAME'] = long_name
 
     return test_metadata
@@ -644,8 +649,8 @@ def _detect_and_print_issues(build_yaml_like: BuildYaml) -> None:
         if tgt['build'] == 'test':
             for src in tgt['src']:
                 if src.startswith('src/') and not src.endswith('.proto'):
-                    print('source file from under "src/" tree used in test ' +
-                          tgt['name'] + ': ' + src)
+                    print(('source file from under "src/" tree used in test ' +
+                           tgt['name'] + ': ' + src))
 
 
 # extra metadata that will be used to construct build.yaml
@@ -968,7 +973,7 @@ all_extra_metadata.update(
 #               '_COLLAPSED_PUBLIC_HEADERS': [...],
 #               '_COLLAPSED_HEADERS': [...]
 #             }
-_populate_transitive_metadata(bazel_rules, all_extra_metadata.keys())
+_populate_transitive_metadata(bazel_rules, list(all_extra_metadata.keys()))
 
 # Step 4a: Update the existing test metadata with the updated build metadata.
 # Certain build metadata of certain test targets depend on the transitive
diff --git a/tools/buildgen/plugins/check_attrs.py b/tools/buildgen/plugins/check_attrs.py
index a9acd1ea550..34729ed1686 100644
--- a/tools/buildgen/plugins/check_attrs.py
+++ b/tools/buildgen/plugins/check_attrs.py
@@ -95,7 +95,7 @@ VALID_ATTRIBUTE_KEYS_MAP = {
 def check_attributes(entity, kind, errors):
     attributes = VALID_ATTRIBUTE_KEYS_MAP[kind]
     name = entity.get('name', anything())
-    for key, value in entity.items():
+    for key, value in list(entity.items()):
         if key == 'name':
             continue
         validator = attributes.get(key)
diff --git a/tools/buildgen/plugins/list_api.py b/tools/buildgen/plugins/list_api.py
index c6d78eb1a85..da5ae56126a 100755
--- a/tools/buildgen/plugins/list_api.py
+++ b/tools/buildgen/plugins/list_api.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 
 # Copyright 2016 gRPC authors.
 #
@@ -65,5 +65,6 @@ def mako_plugin(dictionary):
 
 
 if __name__ == '__main__':
-    print(yaml.dump([api for api in list_c_apis(headers_under('include/grpc'))
-                    ]))
+    print(
+        (yaml.dump([api for api in list_c_apis(headers_under('include/grpc'))
+                   ])))
diff --git a/tools/buildgen/plugins/transitive_dependencies.py b/tools/buildgen/plugins/transitive_dependencies.py
index 0ca4f408e3e..97c726b7495 100644
--- a/tools/buildgen/plugins/transitive_dependencies.py
+++ b/tools/buildgen/plugins/transitive_dependencies.py
@@ -53,7 +53,7 @@ def mako_plugin(dictionary):
     """
     lib_map = {lib['name']: lib for lib in dictionary.get('libs')}
 
-    for target_name, target_list in dictionary.items():
+    for target_name, target_list in list(dictionary.items()):
         for target in target_list:
             if isinstance(target, dict):
                 if 'deps' in target or target_name == 'libs':
diff --git a/tools/codegen/core/gen_header_frame.py b/tools/codegen/core/gen_header_frame.py
index eb9b0757550..4545f3e56d1 100755
--- a/tools/codegen/core/gen_header_frame.py
+++ b/tools/codegen/core/gen_header_frame.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 
 # Copyright 2015 gRPC authors.
 #
@@ -141,7 +141,7 @@ if args.hex:
     all_bytes = []
     for line in payload_bytes:
         all_bytes.extend(line)
-    print '{%s}' % ', '.join('0x%02x' % c for c in all_bytes)
+    print(('{%s}' % ', '.join('0x%02x' % c for c in all_bytes)))
 else:
     for line in payload_bytes:
-        print esc_c(line)
+        print((esc_c(line)))
diff --git a/tools/codegen/core/gen_server_registered_method_bad_client_test_body.py b/tools/codegen/core/gen_server_registered_method_bad_client_test_body.py
index 14fbb9ca529..f4f25a69a93 100755
--- a/tools/codegen/core/gen_server_registered_method_bad_client_test_body.py
+++ b/tools/codegen/core/gen_server_registered_method_bad_client_test_body.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 
 # Copyright 2015 gRPC authors.
 #
@@ -49,7 +49,8 @@ for message_length in range(0, 3):
                     ] + payload[0:frame_length]
             text = esc_c(frame)
             if text not in done:
-                print 'GRPC_RUN_BAD_CLIENT_TEST(verifier_%s, PFX_STR %s, %s);' % (
-                    'succeeds' if is_end else 'fails', text,
-                    '0' if is_end else 'GRPC_BAD_CLIENT_DISCONNECT')
+                print(
+                    ('GRPC_RUN_BAD_CLIENT_TEST(verifier_%s, PFX_STR %s, %s);' %
+                     ('succeeds' if is_end else 'fails', text,
+                      '0' if is_end else 'GRPC_BAD_CLIENT_DISCONNECT')))
                 done.add(text)
diff --git a/tools/codegen/core/gen_settings_ids.py b/tools/codegen/core/gen_settings_ids.py
index 36b328c5f16..b860d46375d 100755
--- a/tools/codegen/core/gen_settings_ids.py
+++ b/tools/codegen/core/gen_settings_ids.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 
 # Copyright 2017 gRPC authors.
 #
@@ -14,6 +14,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 import collections
 import sys
 
@@ -57,11 +59,11 @@ C = open('src/core/ext/transport/chttp2/transport/http2_settings.c', 'w')
 # utility: print a big comment block into a set of files
 def put_banner(files, banner):
     for f in files:
-        print >> f, '/*'
+        print('/*', file=f)
         for line in banner:
-            print >> f, ' * %s' % line
-        print >> f, ' */'
-        print >> f
+            print(' * %s' % line, file=f)
+        print(' */', file=f)
+        print(file=f)
 
 
 # copy-paste copyright notice from this file
@@ -84,79 +86,89 @@ put_banner(
     [H, C],
     ["Automatically generated by tools/codegen/core/gen_settings_ids.py"])
 
-print >> H, "#ifndef GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H"
-print >> H, "#define GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H"
-print >> H
-print >> H, "#include <stdint.h>"
-print >> H, "#include <stdbool.h>"
-print >> H
+print("#ifndef GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H",
+      file=H)
+print("#define GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H",
+      file=H)
+print(file=H)
+print("#include <stdint.h>", file=H)
+print("#include <stdbool.h>", file=H)
+print(file=H)
 
-print >> C, "#include \"src/core/ext/transport/chttp2/transport/http2_settings.h\""
-print >> C
-print >> C, "#include <grpc/support/useful.h>"
-print >> C, "#include \"src/core/lib/transport/http2_errors.h\""
-print >> C
+print("#include \"src/core/ext/transport/chttp2/transport/http2_settings.h\"",
+      file=C)
+print(file=C)
+print("#include <grpc/support/useful.h>", file=C)
+print("#include \"src/core/lib/transport/http2_errors.h\"", file=C)
+print(file=C)
 
-p = perfection.hash_parameters(sorted(x.id for x in _SETTINGS.values()))
-print p
+p = perfection.hash_parameters(sorted(x.id for x in list(_SETTINGS.values())))
+print(p)
 
 
 def hash(i):
     i += p.offset
     x = i % p.t
-    y = i / p.t
+    y = i // p.t
     return x + p.r[y]
 
 
 decorated_settings = [
     DecoratedSetting(hash(setting.id), name, setting)
-    for name, setting in _SETTINGS.iteritems()
+    for name, setting in _SETTINGS.items()
 ]
 
-print >> H, 'typedef enum {'
+print('typedef enum {', file=H)
 for decorated_setting in sorted(decorated_settings):
-    print >> H, '  GRPC_CHTTP2_SETTINGS_%s = %d, /* wire id %d */' % (
-        decorated_setting.name, decorated_setting.enum,
-        decorated_setting.setting.id)
-print >> H, '} grpc_chttp2_setting_id;'
-print >> H
-print >> H, '#define GRPC_CHTTP2_NUM_SETTINGS %d' % (
-    max(x.enum for x in decorated_settings) + 1)
+    print('  GRPC_CHTTP2_SETTINGS_%s = %d, /* wire id %d */' %
+          (decorated_setting.name, decorated_setting.enum,
+           decorated_setting.setting.id),
+          file=H)
+print('} grpc_chttp2_setting_id;', file=H)
+print(file=H)
+print('#define GRPC_CHTTP2_NUM_SETTINGS %d' %
+      (max(x.enum for x in decorated_settings) + 1),
+      file=H)
 
-print >> H, 'extern const uint16_t grpc_setting_id_to_wire_id[];'
-print >> C, 'const uint16_t grpc_setting_id_to_wire_id[] = {%s};' % ','.join(
-    '%d' % s for s in p.slots)
-print >> H
-print >> H, "bool grpc_wire_id_to_setting_id(uint32_t wire_id, grpc_chttp2_setting_id *out);"
+print('extern const uint16_t grpc_setting_id_to_wire_id[];', file=H)
+print('const uint16_t grpc_setting_id_to_wire_id[] = {%s};' %
+      ','.join('%d' % s for s in p.slots),
+      file=C)
+print(file=H)
+print(
+    "bool grpc_wire_id_to_setting_id(uint32_t wire_id, grpc_chttp2_setting_id *out);",
+    file=H)
 cgargs = {
     'r': ','.join('%d' % (r if r is not None else 0) for r in p.r),
     't': p.t,
     'offset': abs(p.offset),
     'offset_sign': '+' if p.offset > 0 else '-'
 }
-print >> C, """
+print("""
 bool grpc_wire_id_to_setting_id(uint32_t wire_id, grpc_chttp2_setting_id *out) {
   uint32_t i = wire_id %(offset_sign)s %(offset)d;
   uint32_t x = i %% %(t)d;
   uint32_t y = i / %(t)d;
   uint32_t h = x;
   switch (y) {
-""" % cgargs
+""" % cgargs,
+      file=C)
 for i, r in enumerate(p.r):
     if not r:
         continue
     if r < 0:
-        print >> C, 'case %d: h -= %d; break;' % (i, -r)
+        print('case %d: h -= %d; break;' % (i, -r), file=C)
     else:
-        print >> C, 'case %d: h += %d; break;' % (i, r)
-print >> C, """
+        print('case %d: h += %d; break;' % (i, r), file=C)
+print("""
   }
   *out = (grpc_chttp2_setting_id)h;
   return h < GPR_ARRAY_SIZE(grpc_setting_id_to_wire_id) && grpc_setting_id_to_wire_id[h] == wire_id;
 }
-""" % cgargs
+""" % cgargs,
+      file=C)
 
-print >> H, """
+print("""
 typedef enum {
   GRPC_CHTTP2_CLAMP_INVALID_VALUE,
   GRPC_CHTTP2_DISCONNECT_ON_INVALID_VALUE
@@ -172,26 +184,33 @@ typedef struct {
 } grpc_chttp2_setting_parameters;
 
 extern const grpc_chttp2_setting_parameters grpc_chttp2_settings_parameters[GRPC_CHTTP2_NUM_SETTINGS];
-"""
-print >> C, "const grpc_chttp2_setting_parameters grpc_chttp2_settings_parameters[GRPC_CHTTP2_NUM_SETTINGS] = {"
+""",
+      file=H)
+print(
+    "const grpc_chttp2_setting_parameters grpc_chttp2_settings_parameters[GRPC_CHTTP2_NUM_SETTINGS] = {",
+    file=C)
 i = 0
 for decorated_setting in sorted(decorated_settings):
     while i < decorated_setting.enum:
-        print >> C, "{NULL, 0, 0, 0, GRPC_CHTTP2_DISCONNECT_ON_INVALID_VALUE, GRPC_HTTP2_PROTOCOL_ERROR},"
+        print(
+            "{NULL, 0, 0, 0, GRPC_CHTTP2_DISCONNECT_ON_INVALID_VALUE, GRPC_HTTP2_PROTOCOL_ERROR},",
+            file=C)
         i += 1
-    print >> C, "{\"%s\", %du, %du, %du, GRPC_CHTTP2_%s, GRPC_HTTP2_%s}," % (
+    print("{\"%s\", %du, %du, %du, GRPC_CHTTP2_%s, GRPC_HTTP2_%s}," % (
         decorated_setting.name,
         decorated_setting.setting.default,
         decorated_setting.setting.min,
         decorated_setting.setting.max,
         decorated_setting.setting.on_error.behavior,
         decorated_setting.setting.on_error.code,
-    )
+    ),
+          file=C)
     i += 1
-print >> C, "};"
+print("};", file=C)
 
-print >> H
-print >> H, "#endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H */"
+print(file=H)
+print("#endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H */",
+      file=H)
 
 H.close()
 C.close()
diff --git a/tools/codegen/core/gen_stats_data.py b/tools/codegen/core/gen_stats_data.py
index d1991991de2..9b7ff938557 100755
--- a/tools/codegen/core/gen_stats_data.py
+++ b/tools/codegen/core/gen_stats_data.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 
 # Copyright 2017 gRPC authors.
 #
@@ -14,6 +14,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 import collections
 import ctypes
 import json
@@ -34,10 +36,11 @@ def make_type(name, fields):
 
 
 def c_str(s, encoding='ascii'):
-    if isinstance(s, unicode):
+    if isinstance(s, str):
         s = s.encode(encoding)
     result = ''
     for c in s:
+        c = chr(c) if isinstance(c, int) else c
         if not (32 <= ord(c) < 127) or c in ('\\', '"'):
             result += '\\%03o' % ord(c)
         else:
@@ -81,7 +84,7 @@ def shift_works_until(mapped_bounds, shift_bits):
 
 def find_ideal_shift(mapped_bounds, max_size):
     best = None
-    for shift_bits in reversed(range(0, 64)):
+    for shift_bits in reversed(list(range(0, 64))):
         n = shift_works_until(mapped_bounds, shift_bits)
         if n == 0:
             continue
@@ -94,16 +97,16 @@ def find_ideal_shift(mapped_bounds, max_size):
             best = (shift_bits, n, table_size)
         elif best[1] < n:
             best = (shift_bits, n, table_size)
-    print best
+    print(best)
     return best
 
 
 def gen_map_table(mapped_bounds, shift_data):
     tbl = []
     cur = 0
-    print mapped_bounds
+    print(mapped_bounds)
     mapped_bounds = [x >> shift_data[0] for x in mapped_bounds]
-    print mapped_bounds
+    print(mapped_bounds)
     for i in range(0, mapped_bounds[shift_data[1] - 1]):
         while i > mapped_bounds[cur]:
             cur += 1
@@ -120,7 +123,7 @@ def decl_static_table(values, type):
     for i, vp in enumerate(static_tables):
         if v == vp:
             return i
-    print "ADD TABLE: %s %r" % (type, values)
+    print("ADD TABLE: %s %r" % (type, values))
     r = len(static_tables)
     static_tables.append(v)
     return r
@@ -205,11 +208,11 @@ def gen_bucket_code(histogram):
 # utility: print a big comment block into a set of files
 def put_banner(files, banner):
     for f in files:
-        print >> f, '/*'
+        print('/*', file=f)
         for line in banner:
-            print >> f, ' * %s' % line
-        print >> f, ' */'
-        print >> f
+            print(' * %s' % line, file=f)
+        print(' */', file=f)
+        print(file=f)
 
 
 with open('src/core/lib/debug/stats_data.h', 'w') as H:
@@ -233,77 +236,90 @@ with open('src/core/lib/debug/stats_data.h', 'w') as H:
         [H],
         ["Automatically generated by tools/codegen/core/gen_stats_data.py"])
 
-    print >> H, "#ifndef GRPC_CORE_LIB_DEBUG_STATS_DATA_H"
-    print >> H, "#define GRPC_CORE_LIB_DEBUG_STATS_DATA_H"
-    print >> H
-    print >> H, "#include <grpc/support/port_platform.h>"
-    print >> H
-    print >> H, "#include <inttypes.h>"
-    print >> H, "#include \"src/core/lib/iomgr/exec_ctx.h\""
-    print >> H
+    print("#ifndef GRPC_CORE_LIB_DEBUG_STATS_DATA_H", file=H)
+    print("#define GRPC_CORE_LIB_DEBUG_STATS_DATA_H", file=H)
+    print(file=H)
+    print("#include <grpc/support/port_platform.h>", file=H)
+    print(file=H)
+    print("#include <inttypes.h>", file=H)
+    print("#include \"src/core/lib/iomgr/exec_ctx.h\"", file=H)
+    print(file=H)
 
     for typename, instances in sorted(inst_map.items()):
-        print >> H, "typedef enum {"
+        print("typedef enum {", file=H)
         for inst in instances:
-            print >> H, "  GRPC_STATS_%s_%s," % (typename.upper(),
-                                                 inst.name.upper())
-        print >> H, "  GRPC_STATS_%s_COUNT" % (typename.upper())
-        print >> H, "} grpc_stats_%ss;" % (typename.lower())
-        print >> H, "extern const char *grpc_stats_%s_name[GRPC_STATS_%s_COUNT];" % (
-            typename.lower(), typename.upper())
-        print >> H, "extern const char *grpc_stats_%s_doc[GRPC_STATS_%s_COUNT];" % (
-            typename.lower(), typename.upper())
+            print("  GRPC_STATS_%s_%s," % (typename.upper(), inst.name.upper()),
+                  file=H)
+        print("  GRPC_STATS_%s_COUNT" % (typename.upper()), file=H)
+        print("} grpc_stats_%ss;" % (typename.lower()), file=H)
+        print("extern const char *grpc_stats_%s_name[GRPC_STATS_%s_COUNT];" %
+              (typename.lower(), typename.upper()),
+              file=H)
+        print("extern const char *grpc_stats_%s_doc[GRPC_STATS_%s_COUNT];" %
+              (typename.lower(), typename.upper()),
+              file=H)
 
     histo_start = []
     histo_buckets = []
     histo_bucket_boundaries = []
 
-    print >> H, "typedef enum {"
+    print("typedef enum {", file=H)
     first_slot = 0
     for histogram in inst_map['Histogram']:
         histo_start.append(first_slot)
         histo_buckets.append(histogram.buckets)
-        print >> H, "  GRPC_STATS_HISTOGRAM_%s_FIRST_SLOT = %d," % (
-            histogram.name.upper(), first_slot)
-        print >> H, "  GRPC_STATS_HISTOGRAM_%s_BUCKETS = %d," % (
-            histogram.name.upper(), histogram.buckets)
+        print("  GRPC_STATS_HISTOGRAM_%s_FIRST_SLOT = %d," %
+              (histogram.name.upper(), first_slot),
+              file=H)
+        print("  GRPC_STATS_HISTOGRAM_%s_BUCKETS = %d," %
+              (histogram.name.upper(), histogram.buckets),
+              file=H)
         first_slot += histogram.buckets
-    print >> H, "  GRPC_STATS_HISTOGRAM_BUCKETS = %d" % first_slot
-    print >> H, "} grpc_stats_histogram_constants;"
+    print("  GRPC_STATS_HISTOGRAM_BUCKETS = %d" % first_slot, file=H)
+    print("} grpc_stats_histogram_constants;", file=H)
 
-    print >> H, "#if defined(GRPC_COLLECT_STATS) || !defined(NDEBUG)"
+    print("#if defined(GRPC_COLLECT_STATS) || !defined(NDEBUG)", file=H)
     for ctr in inst_map['Counter']:
-        print >> H, ("#define GRPC_STATS_INC_%s() " +
-                     "GRPC_STATS_INC_COUNTER(GRPC_STATS_COUNTER_%s)") % (
-                         ctr.name.upper(), ctr.name.upper())
+        print(("#define GRPC_STATS_INC_%s() " +
+               "GRPC_STATS_INC_COUNTER(GRPC_STATS_COUNTER_%s)") %
+              (ctr.name.upper(), ctr.name.upper()),
+              file=H)
     for histogram in inst_map['Histogram']:
-        print >> H, "#define GRPC_STATS_INC_%s(value) grpc_stats_inc_%s( (int)(value))" % (
-            histogram.name.upper(), histogram.name.lower())
-        print >> H, "void grpc_stats_inc_%s(int x);" % histogram.name.lower()
+        print(
+            "#define GRPC_STATS_INC_%s(value) grpc_stats_inc_%s( (int)(value))"
+            % (histogram.name.upper(), histogram.name.lower()),
+            file=H)
+        print("void grpc_stats_inc_%s(int x);" % histogram.name.lower(), file=H)
 
-    print >> H, "#else"
+    print("#else", file=H)
     for ctr in inst_map['Counter']:
-        print >> H, ("#define GRPC_STATS_INC_%s() ") % (ctr.name.upper())
+        print(("#define GRPC_STATS_INC_%s() ") % (ctr.name.upper()), file=H)
     for histogram in inst_map['Histogram']:
-        print >> H, "#define GRPC_STATS_INC_%s(value)" % (
-            histogram.name.upper())
-    print >> H, "#endif /* defined(GRPC_COLLECT_STATS) || !defined(NDEBUG) */"
+        print("#define GRPC_STATS_INC_%s(value)" % (histogram.name.upper()),
+              file=H)
+    print("#endif /* defined(GRPC_COLLECT_STATS) || !defined(NDEBUG) */",
+          file=H)
 
     for i, tbl in enumerate(static_tables):
-        print >> H, "extern const %s grpc_stats_table_%d[%d];" % (tbl[0], i,
-                                                                  len(tbl[1]))
+        print("extern const %s grpc_stats_table_%d[%d];" %
+              (tbl[0], i, len(tbl[1])),
+              file=H)
 
-    print >> H, "extern const int grpc_stats_histo_buckets[%d];" % len(
-        inst_map['Histogram'])
-    print >> H, "extern const int grpc_stats_histo_start[%d];" % len(
-        inst_map['Histogram'])
-    print >> H, "extern const int *const grpc_stats_histo_bucket_boundaries[%d];" % len(
-        inst_map['Histogram'])
-    print >> H, "extern void (*const grpc_stats_inc_histogram[%d])(int x);" % len(
-        inst_map['Histogram'])
+    print("extern const int grpc_stats_histo_buckets[%d];" %
+          len(inst_map['Histogram']),
+          file=H)
+    print("extern const int grpc_stats_histo_start[%d];" %
+          len(inst_map['Histogram']),
+          file=H)
+    print("extern const int *const grpc_stats_histo_bucket_boundaries[%d];" %
+          len(inst_map['Histogram']),
+          file=H)
+    print("extern void (*const grpc_stats_inc_histogram[%d])(int x);" %
+          len(inst_map['Histogram']),
+          file=H)
 
-    print >> H
-    print >> H, "#endif /* GRPC_CORE_LIB_DEBUG_STATS_DATA_H */"
+    print(file=H)
+    print("#endif /* GRPC_CORE_LIB_DEBUG_STATS_DATA_H */", file=H)
 
 with open('src/core/lib/debug/stats_data.cc', 'w') as C:
     # copy-paste copyright notice from this file
@@ -326,13 +342,13 @@ with open('src/core/lib/debug/stats_data.cc', 'w') as C:
         [C],
         ["Automatically generated by tools/codegen/core/gen_stats_data.py"])
 
-    print >> C, "#include <grpc/support/port_platform.h>"
-    print >> C
-    print >> C, "#include \"src/core/lib/debug/stats.h\""
-    print >> C, "#include \"src/core/lib/debug/stats_data.h\""
-    print >> C, "#include \"src/core/lib/gpr/useful.h\""
-    print >> C, "#include \"src/core/lib/iomgr/exec_ctx.h\""
-    print >> C
+    print("#include <grpc/support/port_platform.h>", file=C)
+    print(file=C)
+    print("#include \"src/core/lib/debug/stats.h\"", file=C)
+    print("#include \"src/core/lib/debug/stats_data.h\"", file=C)
+    print("#include \"src/core/lib/gpr/useful.h\"", file=C)
+    print("#include \"src/core/lib/iomgr/exec_ctx.h\"", file=C)
+    print(file=C)
 
     histo_code = []
     for histogram in inst_map['Histogram']:
@@ -341,36 +357,45 @@ with open('src/core/lib/debug/stats_data.cc', 'w') as C:
         histo_code.append(code)
 
     for typename, instances in sorted(inst_map.items()):
-        print >> C, "const char *grpc_stats_%s_name[GRPC_STATS_%s_COUNT] = {" % (
-            typename.lower(), typename.upper())
+        print("const char *grpc_stats_%s_name[GRPC_STATS_%s_COUNT] = {" %
+              (typename.lower(), typename.upper()),
+              file=C)
         for inst in instances:
-            print >> C, "  %s," % c_str(inst.name)
-        print >> C, "};"
-        print >> C, "const char *grpc_stats_%s_doc[GRPC_STATS_%s_COUNT] = {" % (
-            typename.lower(), typename.upper())
+            print("  %s," % c_str(inst.name), file=C)
+        print("};", file=C)
+        print("const char *grpc_stats_%s_doc[GRPC_STATS_%s_COUNT] = {" %
+              (typename.lower(), typename.upper()),
+              file=C)
         for inst in instances:
-            print >> C, "  %s," % c_str(inst.doc)
-        print >> C, "};"
+            print("  %s," % c_str(inst.doc), file=C)
+        print("};", file=C)
 
     for i, tbl in enumerate(static_tables):
-        print >> C, "const %s grpc_stats_table_%d[%d] = {%s};" % (
-            tbl[0], i, len(tbl[1]), ','.join('%s' % x for x in tbl[1]))
+        print("const %s grpc_stats_table_%d[%d] = {%s};" %
+              (tbl[0], i, len(tbl[1]), ','.join('%s' % x for x in tbl[1])),
+              file=C)
 
     for histogram, code in zip(inst_map['Histogram'], histo_code):
-        print >> C, ("void grpc_stats_inc_%s(int value) {%s}") % (
-            histogram.name.lower(), code)
+        print(("void grpc_stats_inc_%s(int value) {%s}") %
+              (histogram.name.lower(), code),
+              file=C)
 
-    print >> C, "const int grpc_stats_histo_buckets[%d] = {%s};" % (len(
-        inst_map['Histogram']), ','.join('%s' % x for x in histo_buckets))
-    print >> C, "const int grpc_stats_histo_start[%d] = {%s};" % (len(
-        inst_map['Histogram']), ','.join('%s' % x for x in histo_start))
-    print >> C, "const int *const grpc_stats_histo_bucket_boundaries[%d] = {%s};" % (
-        len(inst_map['Histogram']), ','.join(
-            'grpc_stats_table_%d' % x for x in histo_bucket_boundaries))
-    print >> C, "void (*const grpc_stats_inc_histogram[%d])(int x) = {%s};" % (
-        len(inst_map['Histogram']), ','.join(
-            'grpc_stats_inc_%s' % histogram.name.lower()
-            for histogram in inst_map['Histogram']))
+    print(
+        "const int grpc_stats_histo_buckets[%d] = {%s};" %
+        (len(inst_map['Histogram']), ','.join('%s' % x for x in histo_buckets)),
+        file=C)
+    print("const int grpc_stats_histo_start[%d] = {%s};" %
+          (len(inst_map['Histogram']), ','.join('%s' % x for x in histo_start)),
+          file=C)
+    print("const int *const grpc_stats_histo_bucket_boundaries[%d] = {%s};" %
+          (len(inst_map['Histogram']), ','.join(
+              'grpc_stats_table_%d' % x for x in histo_bucket_boundaries)),
+          file=C)
+    print("void (*const grpc_stats_inc_histogram[%d])(int x) = {%s};" %
+          (len(inst_map['Histogram']), ','.join(
+              'grpc_stats_inc_%s' % histogram.name.lower()
+              for histogram in inst_map['Histogram'])),
+          file=C)
 
 # patch qps_test bigquery schema
 RECORD_EXPLICIT_PERCENTILES = [50, 95, 99]
@@ -438,39 +463,56 @@ with open('tools/run_tests/performance/massage_qps_stats.py', 'w') as P:
                 break
         for line in my_source:
             if line[0] == '#':
-                print >> P, line.rstrip()
+                print(line.rstrip(), file=P)
                 break
         for line in my_source:
             if line[0] != '#':
                 break
-            print >> P, line.rstrip()
+            print(line.rstrip(), file=P)
 
-    print >> P
-    print >> P, '# Autogenerated by tools/codegen/core/gen_stats_data.py'
-    print >> P
+    print(file=P)
+    print('# Autogenerated by tools/codegen/core/gen_stats_data.py', file=P)
+    print(file=P)
 
-    print >> P, 'import massage_qps_stats_helpers'
+    print('import massage_qps_stats_helpers', file=P)
 
-    print >> P, 'def massage_qps_stats(scenario_result):'
-    print >> P, '  for stats in scenario_result["serverStats"] + scenario_result["clientStats"]:'
-    print >> P, '    if "coreStats" in stats:'
-    print >> P, '      # Get rid of the "coreStats" element and replace it by statistics'
-    print >> P, '      # that correspond to columns in the bigquery schema.'
-    print >> P, '      core_stats = stats["coreStats"]'
-    print >> P, '      del stats["coreStats"]'
+    print('def massage_qps_stats(scenario_result):', file=P)
+    print(
+        '  for stats in scenario_result["serverStats"] + scenario_result["clientStats"]:',
+        file=P)
+    print('    if "coreStats" in stats:', file=P)
+    print(
+        '      # Get rid of the "coreStats" element and replace it by statistics',
+        file=P)
+    print('      # that correspond to columns in the bigquery schema.', file=P)
+    print('      core_stats = stats["coreStats"]', file=P)
+    print('      del stats["coreStats"]', file=P)
     for counter in inst_map['Counter']:
-        print >> P, '      stats["core_%s"] = massage_qps_stats_helpers.counter(core_stats, "%s")' % (
-            counter.name, counter.name)
+        print(
+            '      stats["core_%s"] = massage_qps_stats_helpers.counter(core_stats, "%s")'
+            % (counter.name, counter.name),
+            file=P)
     for i, histogram in enumerate(inst_map['Histogram']):
-        print >> P, '      h = massage_qps_stats_helpers.histogram(core_stats, "%s")' % histogram.name
-        print >> P, '      stats["core_%s"] = ",".join("%%f" %% x for x in h.buckets)' % histogram.name
-        print >> P, '      stats["core_%s_bkts"] = ",".join("%%f" %% x for x in h.boundaries)' % histogram.name
+        print(
+            '      h = massage_qps_stats_helpers.histogram(core_stats, "%s")' %
+            histogram.name,
+            file=P)
+        print(
+            '      stats["core_%s"] = ",".join("%%f" %% x for x in h.buckets)' %
+            histogram.name,
+            file=P)
+        print(
+            '      stats["core_%s_bkts"] = ",".join("%%f" %% x for x in h.boundaries)'
+            % histogram.name,
+            file=P)
         for pctl in RECORD_EXPLICIT_PERCENTILES:
-            print >> P, '      stats["core_%s_%dp"] = massage_qps_stats_helpers.percentile(h.buckets, %d, h.boundaries)' % (
-                histogram.name, pctl, pctl)
+            print(
+                '      stats["core_%s_%dp"] = massage_qps_stats_helpers.percentile(h.buckets, %d, h.boundaries)'
+                % (histogram.name, pctl, pctl),
+                file=P)
 
 with open('src/core/lib/debug/stats_data_bq_schema.sql', 'w') as S:
     columns = []
     for counter in inst_map['Counter']:
         columns.append(('%s_per_iteration' % counter.name, 'FLOAT'))
-    print >> S, ',\n'.join('%s:%s' % x for x in columns)
+    print(',\n'.join('%s:%s' % x for x in columns), file=S)
diff --git a/tools/debug/core/chttp2_ref_leak.py b/tools/debug/core/chttp2_ref_leak.py
index 177c1162e96..9403853a91b 100755
--- a/tools/debug/core/chttp2_ref_leak.py
+++ b/tools/debug/core/chttp2_ref_leak.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2017 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -39,6 +39,6 @@ for line in sys.stdin:
         else:
             outstanding[m.group(2)].remove(m.group(3))
 
-for obj, remaining in outstanding.items():
+for obj, remaining in list(outstanding.items()):
     if remaining:
-        print 'LEAKED: %s %r' % (obj, remaining)
+        print(('LEAKED: %s %r' % (obj, remaining)))
diff --git a/tools/debug/core/error_ref_leak.py b/tools/debug/core/error_ref_leak.py
index 2c0bacf4450..d65ecabfab1 100644
--- a/tools/debug/core/error_ref_leak.py
+++ b/tools/debug/core/error_ref_leak.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 #
 # Copyright 2017 gRPC authors.
 #
@@ -44,4 +44,4 @@ for line in data:
             assert (err in errs)
             errs.remove(err)
 
-print "leaked:", errs
+print(("leaked:", errs))
diff --git a/tools/distrib/c-ish/check_documentation.py b/tools/distrib/c-ish/check_documentation.py
index d17d7ebca09..b653c339f21 100755
--- a/tools/distrib/c-ish/check_documentation.py
+++ b/tools/distrib/c-ish/check_documentation.py
@@ -41,13 +41,13 @@ for target_dir in _TARGET_DIRS:
     for root, dirs, filenames in os.walk(target_dir):
         if 'README.md' not in filenames:
             if not printed_banner:
-                print 'Missing README.md'
-                print '================='
+                print('Missing README.md')
+                print('=================')
                 printed_banner = True
-            print root
+            print(root)
             errors += 1
 if printed_banner:
-    print
+    print()
 printed_banner = False
 for target_dir in _TARGET_DIRS:
     for root, dirs, filenames in os.walk(target_dir):
@@ -59,10 +59,10 @@ for target_dir in _TARGET_DIRS:
                 contents = f.read()
             if '\\file' not in contents:
                 if not printed_banner:
-                    print 'Missing \\file comment'
-                    print '======================'
+                    print('Missing \\file comment')
+                    print('======================')
                     printed_banner = True
-                print path
+                print(path)
                 errors += 1
 
 assert errors == 0, 'error count = %d' % errors
diff --git a/tools/distrib/check_copyright.py b/tools/distrib/check_copyright.py
index 03eb6a17ee8..d9b2910e9fb 100755
--- a/tools/distrib/check_copyright.py
+++ b/tools/distrib/check_copyright.py
@@ -140,7 +140,7 @@ RE_LICENSE = dict(
     (k, r'\n'.join(LICENSE_PREFIX_RE[k] +
                    (RE_YEAR if re.search(RE_YEAR, line) else re.escape(line))
                    for line in LICENSE_NOTICE))
-    for k, v in LICENSE_PREFIX_RE.items())
+    for k, v in list(LICENSE_PREFIX_RE.items()))
 
 YEAR = datetime.datetime.now().year
 
@@ -168,7 +168,7 @@ LICENSE_TEXT = dict(
     (k,
      join_license_text(LICENSE_PREFIX_TEXT[k][0], LICENSE_PREFIX_TEXT[k][1],
                        LICENSE_PREFIX_TEXT[k][2], LICENSE_NOTICE))
-    for k, v in LICENSE_PREFIX_TEXT.items())
+    for k, v in list(LICENSE_PREFIX_TEXT.items()))
 
 if args.precommit:
     FILE_LIST_COMMAND = 'git status -z | grep -Poz \'(?<=^[MARC][MARCD ] )[^\s]+\''
@@ -195,7 +195,7 @@ def log(cond, why, filename):
     if not cond:
         return
     if args.output == 'details':
-        print('%s: %s' % (why, filename))
+        print(('%s: %s' % (why, filename)))
     else:
         print(filename)
 
diff --git a/tools/distrib/check_include_guards.py b/tools/distrib/check_include_guards.py
index 9776c476c5e..058cba1b653 100755
--- a/tools/distrib/check_include_guards.py
+++ b/tools/distrib/check_include_guards.py
@@ -66,15 +66,15 @@ class GuardValidator(object):
                         if c_core_header else '#endif  // {2}')
         if not match_txt:
             print(
-                invalid_guards_msg_template.format(fpath, regexp.pattern,
-                                                   build_valid_guard(fpath)))
+                (invalid_guards_msg_template.format(fpath, regexp.pattern,
+                                                    build_valid_guard(fpath))))
             return fcontents
 
-        print(('{}: Wrong preprocessor guards (RE {}):'
-               '\n\tFound {}, expected {}').format(fpath, regexp.pattern,
-                                                   match_txt, correct))
+        print((('{}: Wrong preprocessor guards (RE {}):'
+                '\n\tFound {}, expected {}').format(fpath, regexp.pattern,
+                                                    match_txt, correct)))
         if fix:
-            print('Fixing {}...\n'.format(fpath))
+            print(('Fixing {}...\n'.format(fpath)))
             fixed_fcontents = re.sub(match_txt, correct, fcontents)
             if fixed_fcontents:
                 self.failed = False
@@ -91,7 +91,7 @@ class GuardValidator(object):
 
         match = self.ifndef_re.search(fcontents)
         if not match:
-            print('something drastically wrong with: %s' % fpath)
+            print(('something drastically wrong with: %s' % fpath))
             return False  # failed
         if match.lastindex is None:
             # No ifndef. Request manual addition with hints
diff --git a/tools/distrib/python/check_grpcio_tools.py b/tools/distrib/python/check_grpcio_tools.py
index 25751ca4962..376ea55d226 100755
--- a/tools/distrib/python/check_grpcio_tools.py
+++ b/tools/distrib/python/check_grpcio_tools.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2015 gRPC authors.
 #
diff --git a/tools/distrib/python/docgen.py b/tools/distrib/python/docgen.py
index dc4372ae8f0..9cbd6bbab6e 100755
--- a/tools/distrib/python/docgen.py
+++ b/tools/distrib/python/docgen.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
diff --git a/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py b/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py
index 74ea853fa57..ce7b82487f7 100644
--- a/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py
+++ b/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2016 gRPC authors.
 #
diff --git a/tools/distrib/python/make_grpcio_tools.py b/tools/distrib/python/make_grpcio_tools.py
index a6fdae28d73..8b0d26b07a7 100755
--- a/tools/distrib/python/make_grpcio_tools.py
+++ b/tools/distrib/python/make_grpcio_tools.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2016 gRPC authors.
 #
@@ -94,13 +94,13 @@ def protobuf_submodule_commit_hash():
     os.chdir(GRPC_PROTOBUF_SUBMODULE_ROOT)
     output = subprocess.check_output(['git', 'rev-parse', 'HEAD'])
     os.chdir(cwd)
-    return output.splitlines()[0].strip()
+    return output.decode("ascii").splitlines()[0].strip()
 
 
 def bazel_query(query):
     print('Running "bazel query %s"' % query)
     output = subprocess.check_output([BAZEL_DEPS, query])
-    return output.splitlines()
+    return output.decode("ascii").splitlines()
 
 
 def get_deps():
diff --git a/tools/distrib/python/submit.py b/tools/distrib/python/submit.py
deleted file mode 100755
index 6ce6462b34e..00000000000
--- a/tools/distrib/python/submit.py
+++ /dev/null
@@ -1,93 +0,0 @@
-#!/usr/bin/env python2.7
-# Copyright 2015 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import argparse
-import os
-import shutil
-import subprocess
-
-parser = argparse.ArgumentParser(
-    description='Submit the package to a PyPI repository.')
-parser.add_argument('--repository',
-                    '-r',
-                    metavar='r',
-                    type=str,
-                    default='pypi',
-                    help='The repository to push the package to. '
-                    'Ensure the value appears in your .pypirc file. '
-                    'Defaults to "pypi".')
-parser.add_argument('--identity',
-                    '-i',
-                    metavar='i',
-                    type=str,
-                    help='GPG identity to sign the files with.')
-parser.add_argument(
-    '--username',
-    '-u',
-    metavar='u',
-    type=str,
-    help='Username to authenticate with the repository. Not needed if you have '
-    'configured your .pypirc to include your username.')
-parser.add_argument(
-    '--password',
-    '-p',
-    metavar='p',
-    type=str,
-    help='Password to authenticate with the repository. Not needed if you have '
-    'configured your .pypirc to include your password.')
-parser.add_argument(
-    '--bdist',
-    '-b',
-    action='store_true',
-    help='Generate a binary distribution (wheel) for the current OS.')
-parser.add_argument(
-    '--dist-args',
-    type=str,
-    help='Additional arguments to pass to the *dist setup.py command.')
-args = parser.parse_args()
-
-# Move to the root directory of Python GRPC.
-pkgdir = os.path.join(os.path.dirname(os.path.abspath(__file__)), '../../../')
-# Remove previous distributions; they somehow confuse twine.
-try:
-    shutil.rmtree(os.path.join(pkgdir, 'dist/'))
-except:
-    pass
-
-# Build the Cython C files
-build_env = os.environ.copy()
-build_env['GRPC_PYTHON_BUILD_WITH_CYTHON'] = "1"
-cmd = ['python', 'setup.py', 'build_ext', '--inplace']
-subprocess.call(cmd, cwd=pkgdir, env=build_env)
-
-# Make the push.
-if args.bdist:
-    cmd = ['python', 'setup.py', 'bdist_wheel']
-else:
-    cmd = ['python', 'setup.py', 'sdist']
-if args.dist_args:
-    cmd += args.dist_args.split()
-subprocess.call(cmd, cwd=pkgdir)
-
-cmd = ['twine', 'upload', '-r', args.repository]
-if args.identity is not None:
-    cmd.extend(['-i', args.identity])
-if args.username is not None:
-    cmd.extend(['-u', args.username])
-if args.password is not None:
-    cmd.extend(['-p', args.password])
-cmd.append('dist/*')
-
-subprocess.call(cmd, cwd=pkgdir)
diff --git a/tools/distrib/run_clang_tidy.py b/tools/distrib/run_clang_tidy.py
index 2c02ccddd5f..7305c785a7d 100755
--- a/tools/distrib/run_clang_tidy.py
+++ b/tools/distrib/run_clang_tidy.py
@@ -59,10 +59,10 @@ if args.only_changed:
         ['git', 'diff', 'origin/master', 'HEAD', '--name-only'])
     for line in output.decode('ascii').splitlines(False):
         if line in orig_files:
-            print("check: %s" % line)
+            print(("check: %s" % line))
             actual_files.append(line)
         else:
-            print("skip: %s - not in the build" % line)
+            print(("skip: %s - not in the build" % line))
     args.files = actual_files
 
 jobs = []
diff --git a/tools/gcp/github_stats_tracking/app.yaml b/tools/gcp/github_stats_tracking/app.yaml
deleted file mode 100644
index b0fa5573649..00000000000
--- a/tools/gcp/github_stats_tracking/app.yaml
+++ /dev/null
@@ -1,13 +0,0 @@
-runtime: python27
-api_version: 1
-threadsafe: true
-
-service: github-stats-tracking
-
-handlers:
-- url: /.*
-  script: main.app
-
-libraries:
-- name: ssl
-  version: latest
diff --git a/tools/gcp/github_stats_tracking/appengine_config.py b/tools/gcp/github_stats_tracking/appengine_config.py
deleted file mode 100644
index 086be2aefff..00000000000
--- a/tools/gcp/github_stats_tracking/appengine_config.py
+++ /dev/null
@@ -1,19 +0,0 @@
-# Copyright 2019 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-# appengine_config.py
-from google.appengine.ext import vendor
-
-# Add any libraries install in the "lib" folder.
-vendor.add('lib')
diff --git a/tools/gcp/github_stats_tracking/cron.yaml b/tools/gcp/github_stats_tracking/cron.yaml
deleted file mode 100644
index b5b36be92c6..00000000000
--- a/tools/gcp/github_stats_tracking/cron.yaml
+++ /dev/null
@@ -1,4 +0,0 @@
-cron:
-- description: "daily github stats tracking job"
-  url: /daily
-  schedule: every 24 hours
diff --git a/tools/gcp/github_stats_tracking/fetch_data.py b/tools/gcp/github_stats_tracking/fetch_data.py
deleted file mode 100644
index ef0b07cd28d..00000000000
--- a/tools/gcp/github_stats_tracking/fetch_data.py
+++ /dev/null
@@ -1,96 +0,0 @@
-# Copyright 2019 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from datetime import datetime
-from datetime import timedelta
-from time import time
-
-from github import Github
-from github import Label
-from google.cloud import bigquery
-
-ACCESS_TOKEN = ""
-
-
-def get_stats_from_github():
-    # Please set the access token properly before deploying.
-    assert ACCESS_TOKEN
-    g = Github(ACCESS_TOKEN)
-    print g.rate_limiting
-    repo = g.get_repo('grpc/grpc')
-
-    LABEL_LANG = set(label for label in repo.get_labels()
-                     if label.name.split('/')[0] == 'lang')
-    LABEL_KIND_BUG = repo.get_label('kind/bug')
-    LABEL_PRIORITY_P0 = repo.get_label('priority/P0')
-    LABEL_PRIORITY_P1 = repo.get_label('priority/P1')
-    LABEL_PRIORITY_P2 = repo.get_label('priority/P2')
-
-    def is_untriaged(issue):
-        key_labels = set()
-        for label in issue.labels:
-            label_kind = label.name.split('/')[0]
-            if label_kind in ('lang', 'kind', 'priority'):
-                key_labels.add(label_kind)
-        return len(key_labels) < 3
-
-    untriaged_open_issues = [
-        issue for issue in repo.get_issues(state='open')
-        if issue.pull_request is None and is_untriaged(issue)
-    ]
-    total_bugs = [
-        issue for issue in repo.get_issues(state='all', labels=[LABEL_KIND_BUG])
-        if issue.pull_request is None
-    ]
-
-    lang_to_stats = {}
-    for lang in LABEL_LANG:
-        lang_bugs = filter(lambda bug: lang in bug.labels, total_bugs)
-        closed_bugs = filter(lambda bug: bug.state == 'closed', lang_bugs)
-        open_bugs = filter(lambda bug: bug.state == 'open', lang_bugs)
-        open_p0_bugs = filter(lambda bug: LABEL_PRIORITY_P0 in bug.labels,
-                              open_bugs)
-        open_p1_bugs = filter(lambda bug: LABEL_PRIORITY_P1 in bug.labels,
-                              open_bugs)
-        open_p2_bugs = filter(lambda bug: LABEL_PRIORITY_P2 in bug.labels,
-                              open_bugs)
-        lang_to_stats[lang] = [
-            len(lang_bugs),
-            len(closed_bugs),
-            len(open_bugs),
-            len(open_p0_bugs),
-            len(open_p1_bugs),
-            len(open_p2_bugs)
-        ]
-    return len(untriaged_open_issues), lang_to_stats
-
-
-def insert_stats_to_db(untriaged_open_issues, lang_to_stats):
-    timestamp = time()
-    client = bigquery.Client()
-    dataset_ref = client.dataset('github_issues')
-    table_ref = dataset_ref.table('untriaged_issues')
-    table = client.get_table(table_ref)
-    errors = client.insert_rows(table, [(timestamp, untriaged_open_issues)])
-    table_ref = dataset_ref.table('bug_stats')
-    table = client.get_table(table_ref)
-    rows = []
-    for lang, stats in lang_to_stats.iteritems():
-        rows.append((timestamp, lang.name[5:]) + tuple(stats))
-    errors = client.insert_rows(table, rows)
-
-
-def fetch():
-    untriaged_open_issues, lang_to_stats = get_stats_from_github()
-    insert_stats_to_db(untriaged_open_issues, lang_to_stats)
diff --git a/tools/gcp/github_stats_tracking/main.py b/tools/gcp/github_stats_tracking/main.py
deleted file mode 100644
index eb86f482fcd..00000000000
--- a/tools/gcp/github_stats_tracking/main.py
+++ /dev/null
@@ -1,28 +0,0 @@
-# Copyright 2019 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from fetch_data import fetch
-import webapp2
-
-
-class DailyCron(webapp2.RequestHandler):
-
-    def get(self):
-        fetch()
-        self.response.status = 204
-
-
-app = webapp2.WSGIApplication([
-    ('/daily', DailyCron),
-], debug=True)
diff --git a/tools/gcp/utils/big_query_utils.py b/tools/gcp/utils/big_query_utils.py
index c5a2125c47d..1853e62666e 100755
--- a/tools/gcp/utils/big_query_utils.py
+++ b/tools/gcp/utils/big_query_utils.py
@@ -1,4 +1,3 @@
-#!/usr/bin/env python2.7
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
diff --git a/tools/internal_ci/helper_scripts/prepare_build_linux_rc b/tools/internal_ci/helper_scripts/prepare_build_linux_rc
index 0a4a8491c72..01e9dd71246 100644
--- a/tools/internal_ci/helper_scripts/prepare_build_linux_rc
+++ b/tools/internal_ci/helper_scripts/prepare_build_linux_rc
@@ -40,3 +40,5 @@ fi
 export DOCKERHUB_ORGANIZATION=grpctesting
 
 git submodule update --init
+
+python3 -m pip install six
diff --git a/tools/internal_ci/helper_scripts/prepare_build_windows.bat b/tools/internal_ci/helper_scripts/prepare_build_windows.bat
index fdc7b096420..aacae5c5213 100644
--- a/tools/internal_ci/helper_scripts/prepare_build_windows.bat
+++ b/tools/internal_ci/helper_scripts/prepare_build_windows.bat
@@ -15,7 +15,14 @@
 @rem make sure msys binaries are preferred over cygwin binaries
 @rem set path to python 2.7
 @rem set path to CMake
-set PATH=C:\tools\msys64\usr\bin;C:\Python27;C:\Program Files\CMake\bin;%PATH%
+set PATH=C:\tools\msys64\usr\bin;C:\Python37;C:\Python27;C:\Program Files\CMake\bin;%PATH%
+
+dir C:\Python37\
+
+mklink C:\Python37\python3.exe C:\Python37\python.exe
+
+python --version
+python3 --version
 
 @rem If this is a PR using RUN_TESTS_FLAGS var, then add flags to filter tests
 if defined KOKORO_GITHUB_PULL_REQUEST_NUMBER if defined RUN_TESTS_FLAGS (
@@ -29,8 +36,6 @@ netsh interface ip set dns "Local Area Connection 8" static 169.254.169.254 prim
 netsh interface ip add dnsservers "Local Area Connection 8" 8.8.8.8 index=2
 netsh interface ip add dnsservers "Local Area Connection 8" 8.8.4.4 index=3
 
-@rem Needed for big_query_utils
-python -m pip install google-api-python-client || goto :error
 
 @rem C# prerequisites: Install dotnet SDK
 powershell -File src\csharp\install_dotnet_sdk.ps1 || goto :error
@@ -46,6 +51,9 @@ If "%PREPARE_BUILD_INSTALL_DEPS_PYTHON%" == "true" (
     powershell -File tools\internal_ci\helper_scripts\install_python_interpreters.ps1 || goto :error
 )
 
+@rem Needed for big_query_utils
+python -m pip install google-api-python-client || goto :error
+
 git submodule update --init || goto :error
 
 goto :EOF
diff --git a/tools/internal_ci/linux/aws/grpc_aws_experiment_remote.sh b/tools/internal_ci/linux/aws/grpc_aws_experiment_remote.sh
index 66a661e562f..3e7ad5fa663 100755
--- a/tools/internal_ci/linux/aws/grpc_aws_experiment_remote.sh
+++ b/tools/internal_ci/linux/aws/grpc_aws_experiment_remote.sh
@@ -17,13 +17,13 @@ set -ex
 
 #install ubuntu pre-requisites
 sudo apt update
-sudo apt install -y build-essential autoconf libtool pkg-config cmake python python-pip clang
+sudo apt install -y build-essential autoconf libtool pkg-config cmake python3 python3-pip clang
 sudo pip install six
 
 cd grpc
 
 # without port server running, many tests will fail
-python tools/run_tests/start_port_server.py
+python3 tools/run_tests/start_port_server.py
 
 # build with bazel
 tools/bazel build --config=opt //test/...
diff --git a/tools/internal_ci/linux/aws/grpc_bazel_test_c_cpp_aarch64.sh b/tools/internal_ci/linux/aws/grpc_bazel_test_c_cpp_aarch64.sh
index 92274dfaebb..169876c4e6f 100755
--- a/tools/internal_ci/linux/aws/grpc_bazel_test_c_cpp_aarch64.sh
+++ b/tools/internal_ci/linux/aws/grpc_bazel_test_c_cpp_aarch64.sh
@@ -17,7 +17,7 @@ set -ex
 
 # install pre-requisites for gRPC C core build
 sudo apt update
-sudo apt install -y build-essential autoconf libtool pkg-config cmake python python-pip clang
+sudo apt install -y build-essential autoconf libtool pkg-config cmake python3 python3-pip clang
 sudo pip install six
 
 # install python3.6 and pip
diff --git a/tools/internal_ci/linux/grpc_bazel_on_foundry_base.sh b/tools/internal_ci/linux/grpc_bazel_on_foundry_base.sh
index d5b38de3b51..08fdeb5c5c1 100755
--- a/tools/internal_ci/linux/grpc_bazel_on_foundry_base.sh
+++ b/tools/internal_ci/linux/grpc_bazel_on_foundry_base.sh
@@ -41,7 +41,7 @@ if [ "$UPLOAD_TEST_RESULTS" != "" ]
 then
   # Sleep to let ResultStore finish writing results before querying
   sleep 60
-  python ./tools/run_tests/python_utils/upload_rbe_results.py
+  python3 ./tools/run_tests/python_utils/upload_rbe_results.py
 fi
 
 if [ "$FAILED" != "" ]
diff --git a/tools/internal_ci/linux/grpc_coverage.sh b/tools/internal_ci/linux/grpc_coverage.sh
index a91cffdf989..367d42350ef 100755
--- a/tools/internal_ci/linux/grpc_coverage.sh
+++ b/tools/internal_ci/linux/grpc_coverage.sh
@@ -20,19 +20,19 @@ cd $(dirname $0)/../../..
 
 source tools/internal_ci/helper_scripts/prepare_build_linux_rc
 
-python tools/run_tests/run_tests.py \
+python3 tools/run_tests/run_tests.py \
    -l c c++ -x coverage_cpp/sponge_log.xml \
    --use_docker -t -c gcov -j 2 || FAILED="true"
 
-python tools/run_tests/run_tests.py \
+python3 tools/run_tests/run_tests.py \
    -l python -x coverage_python/sponge_log.xml \
    --use_docker -t -c gcov -j 2 || FAILED="true"
 
-python tools/run_tests/run_tests.py \
+python3 tools/run_tests/run_tests.py \
    -l ruby -x coverage_ruby/sponge_log.xml \
    --use_docker -t -c gcov -j 2 || FAILED="true"
 
-python tools/run_tests/run_tests.py \
+python3 tools/run_tests/run_tests.py \
    -l php -x coverage_php/sponge_log.xml \
    --use_docker -t -c gcov -j 2 || FAILED="true"
   
diff --git a/tools/internal_ci/linux/grpc_xds_k8s.sh b/tools/internal_ci/linux/grpc_xds_k8s.sh
index 71bcdb70122..6f29462d87b 100755
--- a/tools/internal_ci/linux/grpc_xds_k8s.sh
+++ b/tools/internal_ci/linux/grpc_xds_k8s.sh
@@ -100,7 +100,7 @@ run_test() {
   # https://github.com/grpc/grpc/tree/master/tools/run_tests/xds_k8s_test_driver#basic-usage
   local test_name="${1:?Usage: run_test test_name}"
   set -x
-  python -m "tests.${test_name}" \
+  python3 -m "tests.${test_name}" \
     --flagfile="${TEST_DRIVER_FLAGFILE}" \
     --kube_context="${KUBE_CONTEXT}" \
     --server_image="${SERVER_IMAGE_NAME}:${GIT_COMMIT}" \
diff --git a/tools/internal_ci/linux/grpc_xds_k8s_install_test_driver.sh b/tools/internal_ci/linux/grpc_xds_k8s_install_test_driver.sh
index bb333c3f4e5..ae8a5edc9c2 100644
--- a/tools/internal_ci/linux/grpc_xds_k8s_install_test_driver.sh
+++ b/tools/internal_ci/linux/grpc_xds_k8s_install_test_driver.sh
@@ -226,9 +226,9 @@ test_driver_pip_install() {
     source "${venv_dir}/bin/activate"
   fi
 
-  pip install -r requirements.txt
+  python3 -m pip install -r requirements.txt
   echo "Installed Python packages:"
-  pip list
+  python3 -m pip list
 }
 
 #######################################
@@ -254,7 +254,7 @@ test_driver_compile_protos() {
   )
   echo "Generate python code from grpc.testing protos: ${protos[*]}"
   cd "${TEST_DRIVER_REPO_DIR}"
-  python -m grpc_tools.protoc \
+  python3 -m grpc_tools.protoc \
     --proto_path=. \
     --python_out="${TEST_DRIVER_FULL_DIR}" \
     --grpc_python_out="${TEST_DRIVER_FULL_DIR}" \
@@ -345,12 +345,12 @@ kokoro_setup_python_virtual_environment() {
   pyenv virtualenv --no-pip "${py_latest_patch}" k8s_xds_test_runner
   pyenv local k8s_xds_test_runner
   pyenv activate k8s_xds_test_runner
-  python -m ensurepip
+  python3 -m ensurepip
   # pip is fixed to 21.0.1 due to issue https://github.com/pypa/pip/pull/9835
   # internal details: b/186411224
   # TODO(sergiitk): revert https://github.com/grpc/grpc/pull/26087 when 21.1.1 released
-  python -m pip install -U pip==21.0.1
-  pip --version
+  python3 -m pip install -U pip==21.0.1
+  python3 -m pip --version
 }
 
 #######################################
diff --git a/tools/internal_ci/linux/grpc_xds_k8s_lb.sh b/tools/internal_ci/linux/grpc_xds_k8s_lb.sh
index 606a2541f83..68d68cc1332 100755
--- a/tools/internal_ci/linux/grpc_xds_k8s_lb.sh
+++ b/tools/internal_ci/linux/grpc_xds_k8s_lb.sh
@@ -95,7 +95,7 @@ run_test() {
   # Test driver usage:
   # https://github.com/grpc/grpc/tree/master/tools/run_tests/xds_k8s_test_driver#basic-usage
   local test_name="${1:?Usage: run_test test_name}"
-  python -m "tests.${test_name}" \
+  python3 -m "tests.${test_name}" \
     --flagfile="${TEST_DRIVER_FLAGFILE}" \
     --kube_context="${KUBE_CONTEXT}" \
     --secondary_kube_context="${SECONDARY_KUBE_CONTEXT}" \
diff --git a/tools/internal_ci/linux/grpc_xds_k8s_lb_python.sh b/tools/internal_ci/linux/grpc_xds_k8s_lb_python.sh
index 7cf7318e72b..b2389d62b34 100755
--- a/tools/internal_ci/linux/grpc_xds_k8s_lb_python.sh
+++ b/tools/internal_ci/linux/grpc_xds_k8s_lb_python.sh
@@ -96,7 +96,7 @@ run_test() {
   # Test driver usage:
   # https://github.com/grpc/grpc/tree/master/tools/run_tests/xds_k8s_test_driver#basic-usage
   local test_name="${1:?Usage: run_test test_name}"
-  python -m "tests.${test_name}" \
+  python3 -m "tests.${test_name}" \
     --flagfile="${TEST_DRIVER_FLAGFILE}" \
     --kube_context="${KUBE_CONTEXT}" \
     --secondary_kube_context="${SECONDARY_KUBE_CONTEXT}" \
diff --git a/tools/internal_ci/linux/grpc_xds_k8s_python.sh b/tools/internal_ci/linux/grpc_xds_k8s_python.sh
index 7911596bff0..b69406c5812 100755
--- a/tools/internal_ci/linux/grpc_xds_k8s_python.sh
+++ b/tools/internal_ci/linux/grpc_xds_k8s_python.sh
@@ -115,7 +115,7 @@ run_test() {
   # https://github.com/grpc/grpc/tree/master/tools/run_tests/xds_k8s_test_driver#basic-usage
   local test_name="${1:?Usage: run_test test_name}"
   set -x
-  python -m "tests.${test_name}" \
+  python3 -m "tests.${test_name}" \
     --flagfile="${TEST_DRIVER_FLAGFILE}" \
     --kube_context="${KUBE_CONTEXT}" \
     --server_image="${SERVER_IMAGE_NAME}:${GIT_COMMIT}" \
diff --git a/tools/internal_ci/linux/grpc_xds_url_map.sh b/tools/internal_ci/linux/grpc_xds_url_map.sh
index 696ef97d0d0..b606fd5b888 100755
--- a/tools/internal_ci/linux/grpc_xds_url_map.sh
+++ b/tools/internal_ci/linux/grpc_xds_url_map.sh
@@ -85,7 +85,7 @@ run_test() {
   # https://github.com/grpc/grpc/tree/master/tools/run_tests/xds_k8s_test_driver#basic-usage
   local test_name="${1:?Usage: run_test test_name}"
   set -x
-  python -m "tests.${test_name}" \
+  python3 -m "tests.${test_name}" \
     --flagfile="${TEST_DRIVER_FLAGFILE}" \
     --kube_context="${KUBE_CONTEXT}" \
     --client_image="${CLIENT_IMAGE_NAME}:${GIT_COMMIT}" \
diff --git a/tools/internal_ci/linux/grpc_xds_url_map_python.sh b/tools/internal_ci/linux/grpc_xds_url_map_python.sh
index 7316df954f6..f053a84bb66 100755
--- a/tools/internal_ci/linux/grpc_xds_url_map_python.sh
+++ b/tools/internal_ci/linux/grpc_xds_url_map_python.sh
@@ -95,7 +95,7 @@ run_test() {
   # https://github.com/grpc/grpc/tree/master/tools/run_tests/xds_k8s_test_driver#basic-usage
   local test_name="${1:?Usage: run_test test_name}"
   set -x
-  python -m "tests.${test_name}" \
+  python3 -m "tests.${test_name}" \
     --flagfile="${TEST_DRIVER_FLAGFILE}" \
     --kube_context="${KUBE_CONTEXT}" \
     --client_image="${CLIENT_IMAGE_NAME}:${GIT_COMMIT}" \
diff --git a/tools/internal_ci/linux/run_performance_profile_hourly.sh b/tools/internal_ci/linux/run_performance_profile_hourly.sh
index bcb4ea239d2..0b717ac50cb 100755
--- a/tools/internal_ci/linux/run_performance_profile_hourly.sh
+++ b/tools/internal_ci/linux/run_performance_profile_hourly.sh
@@ -19,6 +19,6 @@ cd $(dirname $0)/../../..
 
 ./tools/run_tests/start_port_server.py || true
 
-CPUS=`python -c 'import multiprocessing; print multiprocessing.cpu_count()'`
+CPUS=`python3 -c 'import multiprocessing; print(multiprocessing.cpu_count())'`
 
 tools/run_tests/run_microbenchmark.py --collect summary --bigquery_upload
diff --git a/tools/internal_ci/macos/grpc_run_bazel_c_cpp_tests.sh b/tools/internal_ci/macos/grpc_run_bazel_c_cpp_tests.sh
index bfe1c8c24b1..194f273f675 100644
--- a/tools/internal_ci/macos/grpc_run_bazel_c_cpp_tests.sh
+++ b/tools/internal_ci/macos/grpc_run_bazel_c_cpp_tests.sh
@@ -48,7 +48,7 @@ if [ "$UPLOAD_TEST_RESULTS" != "" ]
 then
   # Sleep to let ResultStore finish writing results before querying
   sleep 60
-  PYTHONHTTPSVERIFY=0 python ./tools/run_tests/python_utils/upload_rbe_results.py
+  PYTHONHTTPSVERIFY=0 python3 ./tools/run_tests/python_utils/upload_rbe_results.py
 fi
 
 if [ "$FAILED" != "" ]
diff --git a/tools/internal_ci/windows/bazel_rbe.bat b/tools/internal_ci/windows/bazel_rbe.bat
index e2ad932b9e2..3fd021b3ef4 100644
--- a/tools/internal_ci/windows/bazel_rbe.bat
+++ b/tools/internal_ci/windows/bazel_rbe.bat
@@ -30,7 +30,7 @@ set BAZEL_EXITCODE=%errorlevel%
 if not "%UPLOAD_TEST_RESULTS%"=="" (
   @rem Sleep to let ResultStore finish writing results before querying
   timeout /t 60 /nobreak
-  python ./tools/run_tests/python_utils/upload_rbe_results.py
+  python3 ./tools/run_tests/python_utils/upload_rbe_results.py
 )
 
 exit /b %BAZEL_EXITCODE%
diff --git a/tools/internal_ci/windows/grpc_run_tests_matrix.bat b/tools/internal_ci/windows/grpc_run_tests_matrix.bat
index 01d60262aac..e69a266532b 100644
--- a/tools/internal_ci/windows/grpc_run_tests_matrix.bat
+++ b/tools/internal_ci/windows/grpc_run_tests_matrix.bat
@@ -20,7 +20,7 @@ If Not "%RUN_TESTS_FLAGS%"=="%RUN_TESTS_FLAGS:python=%" (
 )
 call tools/internal_ci/helper_scripts/prepare_build_windows.bat || exit /b 1
 
-python tools/run_tests/run_tests_matrix.py %RUN_TESTS_FLAGS%
+python3 tools/run_tests/run_tests_matrix.py %RUN_TESTS_FLAGS%
 set RUNTESTS_EXITCODE=%errorlevel%
 
 bash tools/internal_ci/helper_scripts/delete_nonartifacts.sh
diff --git a/tools/interop_matrix/client_matrix.py b/tools/interop_matrix/client_matrix.py
index 83b6be709fe..1a62a9e414b 100644
--- a/tools/interop_matrix/client_matrix.py
+++ b/tools/interop_matrix/client_matrix.py
@@ -1,4 +1,3 @@
-#!/usr/bin/env python2.7
 # Copyright 2017 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
diff --git a/tools/interop_matrix/create_matrix_images.py b/tools/interop_matrix/create_matrix_images.py
index bda9d9bf799..a7e5a4ce969 100755
--- a/tools/interop_matrix/create_matrix_images.py
+++ b/tools/interop_matrix/create_matrix_images.py
@@ -35,13 +35,13 @@ import dockerjob
 import jobset
 
 _IMAGE_BUILDER = 'tools/run_tests/dockerize/build_interop_image.sh'
-_LANGUAGES = client_matrix.LANG_RUNTIME_MATRIX.keys()
+_LANGUAGES = list(client_matrix.LANG_RUNTIME_MATRIX.keys())
 # All gRPC release tags, flattened, deduped and sorted.
 _RELEASES = sorted(
     list(
         set(release
-            for release_dict in client_matrix.LANG_RELEASE_MATRIX.values()
-            for release in release_dict.keys())))
+            for release_dict in list(client_matrix.LANG_RELEASE_MATRIX.values())
+            for release in list(release_dict.keys()))))
 
 # Destination directory inside docker image to keep extra info from build time.
 _BUILD_INFO = '/var/local/build_info'
diff --git a/tools/interop_matrix/run_interop_matrix_tests.py b/tools/interop_matrix/run_interop_matrix_tests.py
index 448dae24b25..42f77d38e2f 100755
--- a/tools/interop_matrix/run_interop_matrix_tests.py
+++ b/tools/interop_matrix/run_interop_matrix_tests.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2017 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -40,13 +40,13 @@ import upload_test_results
 _TEST_TIMEOUT_SECONDS = 60
 _PULL_IMAGE_TIMEOUT_SECONDS = 15 * 60
 _MAX_PARALLEL_DOWNLOADS = 6
-_LANGUAGES = client_matrix.LANG_RUNTIME_MATRIX.keys()
+_LANGUAGES = list(client_matrix.LANG_RUNTIME_MATRIX.keys())
 # All gRPC release tags, flattened, deduped and sorted.
 _RELEASES = sorted(
     list(
         set(release
-            for release_dict in client_matrix.LANG_RELEASE_MATRIX.values()
-            for release in release_dict.keys())))
+            for release_dict in list(client_matrix.LANG_RELEASE_MATRIX.values())
+            for release in list(release_dict.keys()))))
 
 argp = argparse.ArgumentParser(description='Run interop tests.')
 argp.add_argument('-j', '--jobs', default=multiprocessing.cpu_count(), type=int)
@@ -117,7 +117,7 @@ def _get_test_images_for_lang(lang, release_arg, image_path_prefix):
                                                     tag)
             image_tuple = (tag, image_name)
 
-            if not images.has_key(runtime):
+            if runtime not in images:
                 images[runtime] = []
             images[runtime].append(image_tuple)
     return images
diff --git a/tools/mkowners/mkowners.py b/tools/mkowners/mkowners.py
index 030bbf5bcd3..ef09a999e3c 100755
--- a/tools/mkowners/mkowners.py
+++ b/tools/mkowners/mkowners.py
@@ -158,13 +158,13 @@ def expand_directives(root, directives):
             if directive.who not in globs[glob]:
                 globs[glob].append(directive.who)
     # expand owners for intersecting globs
-    sorted_globs = sorted(globs.keys(),
+    sorted_globs = sorted(list(globs.keys()),
                           key=lambda g: len(git_glob(full_dir(root, g))),
                           reverse=True)
     out_globs = collections.OrderedDict()
     for glob_add in sorted_globs:
         who_add = globs[glob_add]
-        pre_items = [i for i in out_globs.items()]
+        pre_items = [i for i in list(out_globs.items())]
         out_globs[glob_add] = who_add.copy()
         for glob_have, who_have in pre_items:
             files_add = git_glob(full_dir(root, glob_add))
@@ -186,8 +186,8 @@ def add_parent_to_globs(parent, globs, globs_dir):
     for owners in owners_data:
         if owners.dir == parent:
             owners_globs = expand_directives(owners.dir, owners.directives)
-            for oglob, oglob_who in owners_globs.items():
-                for gglob, gglob_who in globs.items():
+            for oglob, oglob_who in list(owners_globs.items()):
+                for gglob, gglob_who in list(globs.items()):
                     files_parent = git_glob(full_dir(owners.dir, oglob))
                     files_child = git_glob(full_dir(globs_dir, gglob))
                     intersect = files_parent.intersection(files_child)
@@ -220,7 +220,7 @@ with open(args.out, 'w') as out:
             continue
         globs = expand_directives(head.dir, head.directives)
         add_parent_to_globs(head.parent, globs, head.dir)
-        for glob, owners in globs.items():
+        for glob, owners in list(globs.items()):
             skip = False
             for glob1, owners1, dir1 in reversed(written_globs):
                 files = git_glob(full_dir(head.dir, glob))
diff --git a/tools/profiling/bloat/bloat_diff.py b/tools/profiling/bloat/bloat_diff.py
index e831917078e..c9c82b42a63 100755
--- a/tools/profiling/bloat/bloat_diff.py
+++ b/tools/profiling/bloat/bloat_diff.py
@@ -78,7 +78,7 @@ _build('bloat_diff_new')
 
 if args.diff_base:
     where_am_i = subprocess.check_output(
-        ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).strip()
+        ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).decode().strip()
     # checkout the diff base (="old")
     subprocess.check_call(['git', 'checkout', args.diff_base])
     subprocess.check_call(['git', 'submodule', 'update'])
diff --git a/tools/profiling/ios_bin/binary_size.py b/tools/profiling/ios_bin/binary_size.py
index 76be0c5126d..880c7fcc6c1 100755
--- a/tools/profiling/ios_bin/binary_size.py
+++ b/tools/profiling/ios_bin/binary_size.py
@@ -96,7 +96,7 @@ for frameworks in [False, True]:
     if args.diff_base:
         old = 'old'
         where_am_i = subprocess.check_output(
-            ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).strip()
+            ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).decode().strip()
         subprocess.check_call(['git', 'checkout', '--', '.'])
         subprocess.check_call(['git', 'checkout', args.diff_base])
         subprocess.check_call(['git', 'submodule', 'update', '--force'])
diff --git a/tools/profiling/ios_bin/parse_link_map.py b/tools/profiling/ios_bin/parse_link_map.py
index cfb89a93158..1b0917a0693 100755
--- a/tools/profiling/ios_bin/parse_link_map.py
+++ b/tools/profiling/ios_bin/parse_link_map.py
@@ -95,11 +95,11 @@ def main():
     filename = sys.argv[1]
     core_size, objc_size, boringssl_size, protobuf_size, total_size = parse_link_map(
         filename)
-    print('Core size:{:,}'.format(core_size))
-    print('ObjC size:{:,}'.format(objc_size))
-    print('BoringSSL size:{:,}'.format(boringssl_size))
-    print('Protobuf size:{:,}\n'.format(protobuf_size))
-    print('Total size:{:,}'.format(total_size))
+    print(('Core size:{:,}'.format(core_size)))
+    print(('ObjC size:{:,}'.format(objc_size)))
+    print(('BoringSSL size:{:,}'.format(boringssl_size)))
+    print(('Protobuf size:{:,}\n'.format(protobuf_size)))
+    print(('Total size:{:,}'.format(total_size)))
 
 
 if __name__ == "__main__":
diff --git a/tools/profiling/latency_profile/profile_analyzer.py b/tools/profiling/latency_profile/profile_analyzer.py
index facc024a519..172568e9984 100755
--- a/tools/profiling/latency_profile/profile_analyzer.py
+++ b/tools/profiling/latency_profile/profile_analyzer.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -137,7 +137,7 @@ class CallStack(object):
         self.signature = initial_call_stack_builder.signature
         self.lines = initial_call_stack_builder.lines
         for line in self.lines:
-            for key, val in line.times.items():
+            for key, val in list(line.times.items()):
                 line.times[key] = [val]
 
     def add(self, call_stack_builder):
@@ -146,13 +146,13 @@ class CallStack(object):
         assert len(self.lines) == len(call_stack_builder.lines)
         for lsum, line in zip(self.lines, call_stack_builder.lines):
             assert lsum.tag == line.tag
-            assert lsum.times.keys() == line.times.keys()
-            for k, lst in lsum.times.items():
+            assert list(lsum.times.keys()) == list(line.times.keys())
+            for k, lst in list(lsum.times.items()):
                 lst.append(line.times[k])
 
     def finish(self):
         for line in self.lines:
-            for lst in line.times.values():
+            for lst in list(line.times.values()):
                 lst.sort()
 
 
@@ -175,7 +175,7 @@ with open(args.source) as f:
             del builder[thd]
 time_taken = time.time() - start
 
-call_stacks = sorted(call_stacks.values(),
+call_stacks = sorted(list(call_stacks.values()),
                      key=lambda cs: cs.count,
                      reverse=True)
 total_stacks = 0
@@ -260,7 +260,7 @@ for cs in call_stacks:
         out.write(BANNER[args.fmt] % {
             'count': cs.count,
         })
-    header, _ = zip(*FORMAT)
+    header, _ = list(zip(*FORMAT))
     table = []
     for line in cs.lines:
         fields = []
diff --git a/tools/profiling/qps/qps_diff.py b/tools/profiling/qps/qps_diff.py
index 7d92261e84e..68f3310b1bd 100755
--- a/tools/profiling/qps/qps_diff.py
+++ b/tools/profiling/qps/qps_diff.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 #
 # Copyright 2017 gRPC authors.
 #
@@ -69,7 +69,7 @@ def build(name, jobs):
     subprocess.check_call(['git', 'submodule', 'update'])
     try:
         subprocess.check_call(_make_cmd(jobs))
-    except subprocess.CalledProcessError, e:
+    except subprocess.CalledProcessError as e:
         subprocess.check_call(['make', 'clean'])
         subprocess.check_call(_make_cmd(jobs))
     os.rename('bins', 'qps_diff_%s' % name)
@@ -93,11 +93,11 @@ def _load_qps(fname):
     try:
         with open(fname) as f:
             return json.loads(f.read())['qps']
-    except IOError, e:
-        print("IOError occurred reading file: %s" % fname)
+    except IOError as e:
+        print(("IOError occurred reading file: %s" % fname))
         return None
-    except ValueError, e:
-        print("ValueError occurred reading file: %s" % fname)
+    except ValueError as e:
+        print(("ValueError occurred reading file: %s" % fname))
         return None
 
 
@@ -128,8 +128,8 @@ def diff(scenarios, loops, old, new):
     rows = []
     for sn in scenarios:
         mdn_diff = abs(_median(new_data[sn]) - _median(old_data[sn]))
-        print('%s: %s=%r %s=%r mdn_diff=%r' %
-              (sn, new, new_data[sn], old, old_data[sn], mdn_diff))
+        print(('%s: %s=%r %s=%r mdn_diff=%r' %
+               (sn, new, new_data[sn], old, old_data[sn], mdn_diff)))
         s = bm_speedup.speedup(new_data[sn], old_data[sn], 10e-5)
         if abs(s) > 3 and mdn_diff > 0.5:
             rows.append([sn, '%+d%%' % s])
@@ -145,7 +145,7 @@ def main(args):
 
     if args.diff_base:
         where_am_i = subprocess.check_output(
-            ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).strip()
+            ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).decode().strip()
         subprocess.check_call(['git', 'checkout', args.diff_base])
         try:
             build('old', args.jobs)
@@ -162,7 +162,7 @@ def main(args):
         text = '[qps] Performance differences noted:\n%s' % diff_output
     else:
         text = '[qps] No significant performance differences'
-    print('%s' % text)
+    print(('%s' % text))
     check_on_pr.check_on_pr('QPS', '```\n%s\n```' % text)
 
 
diff --git a/tools/release/release_notes.py b/tools/release/release_notes.py
index 8dc9e0dfe81..98834484a67 100644
--- a/tools/release/release_notes.py
+++ b/tools/release/release_notes.py
@@ -90,7 +90,7 @@ def get_commit_log(prevRelLabel, relBranch):
         "git", "log", "--pretty=oneline", "--committer=GitHub",
         "%s..%s" % (prevRelLabel, relBranch)
     ]
-    print("Running ", " ".join(glg_command))
+    print(("Running ", " ".join(glg_command)))
     return subprocess.check_output(glg_command)
 
 
@@ -98,11 +98,13 @@ def get_pr_data(pr_num):
     """Get the PR data from github. Return 'error' on exception"""
 
     try:
-        from urllib2 import HTTPError
-        from urllib2 import Request
-        from urllib2 import urlopen
+        from urllib.error import HTTPError
+        from urllib.request import Request
+        from urllib.request import urlopen
     except ImportError:
-        import urllib
+        import urllib.error
+        import urllib.parse
+        import urllib.request
         from urllib.request import HTTPError
         from urllib.request import Request
         from urllib.request import urlopen
@@ -116,7 +118,7 @@ def get_pr_data(pr_num):
     except HTTPError as e:
         response = json.loads(e.fp.read().decode('utf-8'))
         if 'message' in response:
-            print(response['message'])
+            print((response['message']))
         response = "error"
     return response
 
@@ -140,10 +142,11 @@ def get_pr_titles(gitLogs):
     langs_pr = defaultdict(list)
     for pr_num in prlist:
         pr_num = str(pr_num)
-        print("---------- getting data for PR " + pr_num)
+        print(("---------- getting data for PR " + pr_num))
         pr = get_pr_data(pr_num)
         if pr == "error":
-            print("\n***ERROR*** Error in getting data for PR " + pr_num + "\n")
+            print(
+                ("\n***ERROR*** Error in getting data for PR " + pr_num + "\n"))
             error_count += 1
             continue
         rl_no_found = False
@@ -162,7 +165,7 @@ def get_pr_titles(gitLogs):
         if not body.endswith("."):
             body = body + "."
         if not pr["merged_by"]:
-            print("\n***ERROR***: No merge_by found for PR " + pr_num + "\n")
+            print(("\n***ERROR***: No merge_by found for PR " + pr_num + "\n"))
             error_count += 1
             continue
 
@@ -173,17 +176,17 @@ def get_pr_titles(gitLogs):
         print(detail)
         #if no RL label
         if not rl_no_found and not rl_yes_found:
-            print("Release notes label missing for " + pr_num)
+            print(("Release notes label missing for " + pr_num))
             langs_pr["nolabel"].append(detail)
         elif rl_yes_found and not lang_found:
-            print("Lang label missing for " + pr_num)
+            print(("Lang label missing for " + pr_num))
             langs_pr["nolang"].append(detail)
         elif rl_no_found:
-            print("'Release notes:no' found for " + pr_num)
+            print(("'Release notes:no' found for " + pr_num))
             langs_pr["notinrel"].append(detail)
         elif rl_yes_found:
-            print("'Release notes:yes' found for " + pr_num + " with lang " +
-                  lang)
+            print(("'Release notes:yes' found for " + pr_num + " with lang " +
+                   lang))
             langs_pr["inrel"].append(detail)
             langs_pr[lang].append(prline)
 
@@ -360,7 +363,7 @@ def main():
     write_draft(langs_pr, file, version, date)
     file.truncate()
     file.close()
-    print("\nDraft notes written to " + filename)
+    print(("\nDraft notes written to " + filename))
 
     filename = os.path.abspath(rel_file)
     if os.path.exists(filename):
@@ -372,7 +375,7 @@ def main():
     write_rel_notes(langs_pr, file, version, name)
     file.truncate()
     file.close()
-    print("\nRelease notes written to " + filename)
+    print(("\nRelease notes written to " + filename))
     if error_count > 0:
         print("\n\n*** Errors were encountered. See log. *********\n")
 
diff --git a/tools/run_tests/artifacts/artifact_targets.py b/tools/run_tests/artifacts/artifact_targets.py
index 55c7ddb6726..1932b46f0ce 100644
--- a/tools/run_tests/artifacts/artifact_targets.py
+++ b/tools/run_tests/artifacts/artifact_targets.py
@@ -38,7 +38,7 @@ def create_docker_jobspec(name,
     environ['ARTIFACTS_OUT'] = 'artifacts/%s' % name
 
     docker_args = []
-    for k, v in environ.items():
+    for k, v in list(environ.items()):
         docker_args += ['-e', '%s=%s' % (k, v)]
     docker_env = {
         'DOCKERFILE_DIR': dockerfile_dir,
diff --git a/tools/run_tests/artifacts/distribtest_targets.py b/tools/run_tests/artifacts/distribtest_targets.py
index 6980e60647f..ab3fc1fe5f6 100644
--- a/tools/run_tests/artifacts/distribtest_targets.py
+++ b/tools/run_tests/artifacts/distribtest_targets.py
@@ -37,7 +37,7 @@ def create_docker_jobspec(name,
         environ['RELATIVE_COPY_PATH'] = copy_rel_path
 
     docker_args = []
-    for k, v in environ.items():
+    for k, v in list(environ.items()):
         docker_args += ['-e', '%s=%s' % (k, v)]
     docker_env = {
         'DOCKERFILE_DIR': dockerfile_dir,
diff --git a/tools/run_tests/artifacts/package_targets.py b/tools/run_tests/artifacts/package_targets.py
index 01dc7c03418..1103c70a8cc 100644
--- a/tools/run_tests/artifacts/package_targets.py
+++ b/tools/run_tests/artifacts/package_targets.py
@@ -32,7 +32,7 @@ def create_docker_jobspec(name,
     environ['RUN_COMMAND'] = shell_command
 
     docker_args = []
-    for k, v in environ.items():
+    for k, v in list(environ.items()):
         docker_args += ['-e', '%s=%s' % (k, v)]
     docker_env = {
         'DOCKERFILE_DIR': dockerfile_dir,
diff --git a/tools/run_tests/lb_interop_tests/gen_build_yaml.py b/tools/run_tests/lb_interop_tests/gen_build_yaml.py
index 7dc313e28d4..c80835d74ab 100755
--- a/tools/run_tests/lb_interop_tests/gen_build_yaml.py
+++ b/tools/run_tests/lb_interop_tests/gen_build_yaml.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -341,6 +341,6 @@ def generate_client_referred_to_backend_multiple_balancers():
 
 all_scenarios += generate_client_referred_to_backend_multiple_balancers()
 
-print(yaml.dump({
+print((yaml.dump({
     'lb_interop_test_scenarios': all_scenarios,
-}))
+})))
diff --git a/tools/run_tests/performance/bq_upload_result.py b/tools/run_tests/performance/bq_upload_result.py
index 9f0179a9c69..d22cba81de8 100755
--- a/tools/run_tests/performance/bq_upload_result.py
+++ b/tools/run_tests/performance/bq_upload_result.py
@@ -25,7 +25,7 @@ import sys
 import time
 import uuid
 
-import massage_qps_stats
+from . import massage_qps_stats
 
 gcp_utils_dir = os.path.abspath(
     os.path.join(os.path.dirname(__file__), '../../gcp/utils'))
diff --git a/tools/run_tests/performance/loadtest_config.py b/tools/run_tests/performance/loadtest_config.py
index a3f1be3b28b..ef534f880de 100755
--- a/tools/run_tests/performance/loadtest_config.py
+++ b/tools/run_tests/performance/loadtest_config.py
@@ -33,10 +33,11 @@ import sys
 from typing import Any, Dict, Iterable, Mapping, Optional, Type
 import uuid
 
-import scenario_config
-import scenario_config_exporter
 import yaml
 
+from . import scenario_config
+from . import scenario_config_exporter
+
 CONFIGURATION_FILE_HEADER_COMMENT = """
 # Load test configurations generated from a template by loadtest_config.py.
 # See documentation below:
diff --git a/tools/run_tests/performance/loadtest_template.py b/tools/run_tests/performance/loadtest_template.py
index e47c0fca874..aefd8d85097 100755
--- a/tools/run_tests/performance/loadtest_template.py
+++ b/tools/run_tests/performance/loadtest_template.py
@@ -29,9 +29,10 @@ import argparse
 import sys
 from typing import Any, Dict, Iterable, List, Mapping, Type
 
-import loadtest_config
 import yaml
 
+from . import loadtest_config
+
 TEMPLATE_FILE_HEADER_COMMENT = """
 # Template generated from load test configurations by loadtest_template.py.
 #
@@ -61,7 +62,7 @@ def insert_worker(worker: Dict[str, Any], workers: List[Dict[str,
 
 def uniquify_workers(workermap: Dict[str, List[Dict[str, Any]]]) -> None:
     """Name workers if there is more than one for the same map key."""
-    for workers in workermap.values():
+    for workers in list(workermap.values()):
         if len(workers) <= 1:
             continue
         for i, worker in enumerate(workers):
diff --git a/tools/run_tests/performance/massage_qps_stats.py b/tools/run_tests/performance/massage_qps_stats.py
index 57de77a7685..da1a7613923 100644
--- a/tools/run_tests/performance/massage_qps_stats.py
+++ b/tools/run_tests/performance/massage_qps_stats.py
@@ -14,7 +14,7 @@
 
 # Autogenerated by tools/codegen/core/gen_stats_data.py
 
-import massage_qps_stats_helpers
+from . import massage_qps_stats_helpers
 
 
 def massage_qps_stats(scenario_result):
diff --git a/tools/run_tests/python_utils/dockerjob.py b/tools/run_tests/python_utils/dockerjob.py
index dcfc5bc43a5..9f4b97bafed 100755
--- a/tools/run_tests/python_utils/dockerjob.py
+++ b/tools/run_tests/python_utils/dockerjob.py
@@ -22,7 +22,7 @@ import tempfile
 import time
 import uuid
 
-import jobset
+from . import jobset
 
 _DEVNULL = open(os.devnull, 'w')
 
@@ -47,7 +47,7 @@ def docker_mapped_port(cid, port, timeout_seconds=15):
         try:
             output = subprocess.check_output('docker port %s %s' % (cid, port),
                                              stderr=_DEVNULL,
-                                             shell=True)
+                                             shell=True).decode()
             return int(output.split(':', 2)[1])
         except subprocess.CalledProcessError as e:
             pass
@@ -61,7 +61,8 @@ def docker_ip_address(cid, timeout_seconds=15):
     while time.time() - started < timeout_seconds:
         cmd = 'docker inspect %s' % cid
         try:
-            output = subprocess.check_output(cmd, stderr=_DEVNULL, shell=True)
+            output = subprocess.check_output(cmd, stderr=_DEVNULL,
+                                             shell=True).decode()
             json_info = json.loads(output)
             assert len(json_info) == 1
             out = json_info[0]['NetworkSettings']['IPAddress']
@@ -82,7 +83,7 @@ def wait_for_healthy(cid, shortname, timeout_seconds):
             output = subprocess.check_output([
                 'docker', 'inspect', '--format="{{.State.Health.Status}}"', cid
             ],
-                                             stderr=_DEVNULL)
+                                             stderr=_DEVNULL).decode()
             if output.strip('\n') == 'healthy':
                 return
         except subprocess.CalledProcessError as e:
diff --git a/tools/run_tests/python_utils/filter_pull_request_tests.py b/tools/run_tests/python_utils/filter_pull_request_tests.py
index 2035aff97c9..1303958813f 100644
--- a/tools/run_tests/python_utils/filter_pull_request_tests.py
+++ b/tools/run_tests/python_utils/filter_pull_request_tests.py
@@ -1,4 +1,3 @@
-#!/usr/bin/env python
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -114,7 +113,7 @@ _ALLOWLIST_DICT = {
 }
 
 # Regex that combines all keys in _ALLOWLIST_DICT
-_ALL_TRIGGERS = "(" + ")|(".join(_ALLOWLIST_DICT.keys()) + ")"
+_ALL_TRIGGERS = "(" + ")|(".join(list(_ALLOWLIST_DICT.keys())) + ")"
 
 # Add all triggers to their respective test suites
 for trigger, test_suites in six.iteritems(_ALLOWLIST_DICT):
diff --git a/tools/run_tests/python_utils/jobset.py b/tools/run_tests/python_utils/jobset.py
index 48503d3843b..99c81038432 100755
--- a/tools/run_tests/python_utils/jobset.py
+++ b/tools/run_tests/python_utils/jobset.py
@@ -44,7 +44,7 @@ def strip_non_ascii_chars(s):
 
 def sanitized_environment(env):
     sanitized = {}
-    for key, value in env.items():
+    for key, value in list(env.items()):
         sanitized[strip_non_ascii_chars(key)] = strip_non_ascii_chars(value)
     return sanitized
 
@@ -130,7 +130,9 @@ def message(tag, msg, explanatory_text=None, do_newline=False):
         try:
             if platform_string() == 'windows' or not sys.stdout.isatty():
                 if explanatory_text:
-                    logging.info(explanatory_text.decode('utf8'))
+                    if isinstance(explanatory_text, bytes):
+                        explanatory_text = explanatory_text.decode('utf8')
+                    logging.info(explanatory_text)
                 logging.info('%s: %s', tag, msg)
             else:
                 sys.stdout.write(
@@ -221,7 +223,7 @@ class JobSpec(object):
 
     def __str__(self):
         return '%s: %s %s' % (self.shortname, ' '.join(
-            '%s=%s' % kv for kv in self.environ.items()), ' '.join(
+            '%s=%s' % kv for kv in list(self.environ.items())), ' '.join(
                 self.cmdline))
 
 
diff --git a/tools/run_tests/python_utils/port_server.py b/tools/run_tests/python_utils/port_server.py
index db1d755ea99..a530165140a 100755
--- a/tools/run_tests/python_utils/port_server.py
+++ b/tools/run_tests/python_utils/port_server.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -193,7 +193,7 @@ class Handler(BaseHTTPRequestHandler):
             now = time.time()
             out = yaml.dump({
                 'pool': pool,
-                'in_use': dict((k, now - v) for k, v in in_use.items())
+                'in_use': dict((k, now - v) for k, v in list(in_use.items()))
             })
             mu.release()
             self.wfile.write(out.encode('ascii'))
diff --git a/tools/run_tests/python_utils/report_utils.py b/tools/run_tests/python_utils/report_utils.py
index 602114b1a5e..ffc59e8d984 100644
--- a/tools/run_tests/python_utils/report_utils.py
+++ b/tools/run_tests/python_utils/report_utils.py
@@ -30,13 +30,15 @@ import six
 def _filter_msg(msg, output_format):
     """Filters out nonprintable and illegal characters from the message."""
     if output_format in ['XML', 'HTML']:
+        if isinstance(msg, bytes):
+            decoded_msg = msg.decode('UTF-8', 'ignore')
+        else:
+            decoded_msg = msg
         # keep whitespaces but remove formfeed and vertical tab characters
         # that make XML report unparsable.
-        if isinstance(msg, bytes):
-            msg = msg.decode('UTF-8', 'ignore')
         filtered_msg = ''.join(
             filter(lambda x: x in string.printable and x != '\f' and x != '\v',
-                   msg))
+                   decoded_msg))
         if output_format == 'HTML':
             filtered_msg = filtered_msg.replace('"', '&quot;')
         return filtered_msg
@@ -138,7 +140,7 @@ def render_interop_html_report(client_langs, server_langs, test_cases,
             'Mako template is not installed. Skipping HTML report generation.')
         return
     except IOError as e:
-        print('Failed to find the template %s: %s' % (template_file, e))
+        print(('Failed to find the template %s: %s' % (template_file, e)))
         return
 
     sorted_test_cases = sorted(test_cases)
@@ -171,7 +173,7 @@ def render_interop_html_report(client_langs, server_langs, test_cases,
         with open(html_file_path, 'w') as output_file:
             mytemplate.render_context(Context(output_file, **args))
     except:
-        print(exceptions.text_error_template().render())
+        print((exceptions.text_error_template().render()))
         raise
 
 
diff --git a/tools/run_tests/python_utils/start_port_server.py b/tools/run_tests/python_utils/start_port_server.py
index b5c615674ca..79867ca5261 100644
--- a/tools/run_tests/python_utils/start_port_server.py
+++ b/tools/run_tests/python_utils/start_port_server.py
@@ -1,4 +1,3 @@
-#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -51,7 +50,7 @@ def start_port_server():
                 sys.executable,  # use the same python binary as this process
                 os.path.abspath('tools/run_tests/python_utils/port_server.py'),
                 'dump_version'
-            ]))
+            ]).decode())
         logging.info('my port server is version %d', current_version)
         running = (version >= current_version)
         if not running:
diff --git a/tools/run_tests/python_utils/upload_rbe_results.py b/tools/run_tests/python_utils/upload_rbe_results.py
index 6eede084d67..3e8038db5c5 100755
--- a/tools/run_tests/python_utils/upload_rbe_results.py
+++ b/tools/run_tests/python_utils/upload_rbe_results.py
@@ -18,10 +18,11 @@ import argparse
 import json
 import os
 import sys
+import urllib.error
+import urllib.parse
+import urllib.request
 import uuid
 
-import urllib2
-
 gcp_utils_dir = os.path.abspath(
     os.path.join(os.path.dirname(__file__), '../../gcp/utils'))
 sys.path.append(gcp_utils_dir)
@@ -121,12 +122,12 @@ def _get_resultstore_data(api_key, invocation_id):
     # that limit, the 'nextPageToken' field is included in the request to get
     # subsequent data, so keep requesting until 'nextPageToken' field is omitted.
     while True:
-        req = urllib2.Request(
+        req = urllib.request.Request(
             url=
             'https://resultstore.googleapis.com/v2/invocations/%s/targets/-/configuredTargets/-/actions?key=%s&pageToken=%s&fields=next_page_token,actions.id,actions.status_attributes,actions.timing,actions.test_action'
             % (invocation_id, api_key, page_token),
             headers={'Content-Type': 'application/json'})
-        results = json.loads(urllib2.urlopen(req).read())
+        results = json.loads(urllib.request.urlopen(req).read())
         all_actions.extend(results['actions'])
         if 'nextPageToken' not in results:
             break
@@ -170,7 +171,8 @@ if __name__ == "__main__":
     if args.resultstore_dump_file:
         with open(args.resultstore_dump_file, 'w') as f:
             json.dump(resultstore_actions, f, indent=4, sort_keys=True)
-        print('Dumped resultstore data to file %s' % args.resultstore_dump_file)
+        print(
+            ('Dumped resultstore data to file %s' % args.resultstore_dump_file))
 
     # google.devtools.resultstore.v2.Action schema:
     # https://github.com/googleapis/googleapis/blob/master/google/devtools/resultstore/v2/action.proto
@@ -256,8 +258,8 @@ if __name__ == "__main__":
                     }
                 })
             except Exception as e:
-                print('Failed to parse test result. Error: %s' % str(e))
-                print(json.dumps(test_case, indent=4))
+                print(('Failed to parse test result. Error: %s' % str(e)))
+                print((json.dumps(test_case, indent=4)))
                 bq_rows.append({
                     'insertId': str(uuid.uuid4()),
                     'json': {
@@ -284,7 +286,7 @@ if __name__ == "__main__":
     if args.bq_dump_file:
         with open(args.bq_dump_file, 'w') as f:
             json.dump(bq_rows, f, indent=4, sort_keys=True)
-        print('Dumped BQ data to file %s' % args.bq_dump_file)
+        print(('Dumped BQ data to file %s' % args.bq_dump_file))
 
     if not args.skip_upload:
         # BigQuery sometimes fails with large uploads, so batch 1,000 rows at a time.
diff --git a/tools/run_tests/run_grpclb_interop_tests.py b/tools/run_tests/run_grpclb_interop_tests.py
index 3368d3d655a..a4df12e9e28 100755
--- a/tools/run_tests/run_grpclb_interop_tests.py
+++ b/tools/run_tests/run_grpclb_interop_tests.py
@@ -171,7 +171,7 @@ def docker_run_cmdline(cmdline, image, docker_args, cwd, environ=None):
     # turn environ into -e docker args
     docker_cmdline = 'docker run -i --rm=true'.split()
     if environ:
-        for k, v in environ.items():
+        for k, v in list(environ.items()):
             docker_cmdline += ['-e', '%s=%s' % (k, v)]
     return docker_cmdline + ['-w', cwd] + docker_args + [image] + cmdline
 
@@ -403,7 +403,7 @@ docker_images = {}
 
 build_jobs = []
 if len(args.language) and args.language[0] == 'all':
-    languages = _LANGUAGES.keys()
+    languages = list(_LANGUAGES.keys())
 else:
     languages = args.language
 for lang_name in languages:
@@ -501,7 +501,7 @@ def run_one_scenario(scenario_config):
         grpclb_ips = []
         shortname_prefix = scenario_config['name']
         # Start backends
-        for i in xrange(len(scenario_config['backend_configs'])):
+        for i in range(len(scenario_config['backend_configs'])):
             backend_config = scenario_config['backend_configs'][i]
             backend_shortname = shortname(shortname_prefix, 'backend_server', i)
             backend_spec = backend_server_jobspec(
@@ -511,7 +511,7 @@ def run_one_scenario(scenario_config):
             backend_addrs.append(
                 '%s:%d' % (backend_job.ip_address(), _BACKEND_SERVER_PORT))
         # Start fallbacks
-        for i in xrange(len(scenario_config['fallback_configs'])):
+        for i in range(len(scenario_config['fallback_configs'])):
             fallback_config = scenario_config['fallback_configs'][i]
             fallback_shortname = shortname(shortname_prefix, 'fallback_server',
                                            i)
@@ -521,7 +521,7 @@ def run_one_scenario(scenario_config):
             server_jobs[fallback_shortname] = fallback_job
             fallback_ips.append(fallback_job.ip_address())
         # Start balancers
-        for i in xrange(len(scenario_config['balancer_configs'])):
+        for i in range(len(scenario_config['balancer_configs'])):
             balancer_config = scenario_config['balancer_configs'][i]
             grpclb_shortname = shortname(shortname_prefix, 'grpclb_server', i)
             grpclb_spec = grpclb_jobspec(balancer_config['transport_sec'],
@@ -582,7 +582,7 @@ def run_one_scenario(scenario_config):
         return num_failures
     finally:
         # Check if servers are still running.
-        for server, job in server_jobs.items():
+        for server, job in list(server_jobs.items()):
             if not job.is_running():
                 print('Server "%s" has exited prematurely.' % server)
         suppress_failure = suppress_server_logs and not args.verbose
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index fb168968e6e..708dac7f70a 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Copyright 2015 gRPC authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -756,8 +756,8 @@ _GRPC_CLIENT_TEST_CASES_FOR_HTTP2_SERVER_TEST_CASES = {
     'no_df_padding_sanity_test': 'large_unary'
 }
 
-_HTTP2_SERVER_TEST_CASES_THAT_USE_GRPC_CLIENTS = _GRPC_CLIENT_TEST_CASES_FOR_HTTP2_SERVER_TEST_CASES.keys(
-)
+_HTTP2_SERVER_TEST_CASES_THAT_USE_GRPC_CLIENTS = list(
+    _GRPC_CLIENT_TEST_CASES_FOR_HTTP2_SERVER_TEST_CASES.keys())
 
 _LANGUAGES_WITH_HTTP2_CLIENTS_FOR_HTTP2_SERVER_TEST_CASES = [
     'java', 'go', 'python', 'c++'
@@ -782,7 +782,7 @@ def docker_run_cmdline(cmdline, image, docker_args=[], cwd=None, environ=None):
 
     # turn environ into -e docker args
     if environ:
-        for k, v in environ.items():
+        for k, v in list(environ.items()):
             docker_cmdline += ['-e', '%s=%s' % (k, v)]
 
     # set working directory
@@ -1208,7 +1208,7 @@ argp.add_argument('--google_default_creds_use_key_file',
                         'google_default_credentials test case, e.g. by '
                         'setting env var GOOGLE_APPLICATION_CREDENTIALS.'))
 argp.add_argument('--prod_servers',
-                  choices=prod_servers.keys(),
+                  choices=list(prod_servers.keys()),
                   default=['default'],
                   nargs='+',
                   help=('The servers to run cloud_to_prod and '
@@ -1549,7 +1549,7 @@ try:
         (server_host, server_port) = server[1].split(':')
         server_addresses[server_name] = (server_host, server_port)
 
-    for server_name, server_address in server_addresses.items():
+    for server_name, server_address in list(server_addresses.items()):
         (server_host, server_port) = server_address
         server_language = _LANGUAGES.get(server_name, None)
         skip_server = []  # test cases unimplemented by server
@@ -1663,7 +1663,7 @@ try:
 
     report_utils.render_junit_xml_report(resultset, _TESTS_XML_REPORT)
 
-    for name, job in resultset.items():
+    for name, job in list(resultset.items()):
         if "http2" in name:
             job[0].http2results = aggregate_http2_results(job[0].message)
 
@@ -1676,7 +1676,7 @@ try:
         sys.exit(0)
 finally:
     # Check if servers are still running.
-    for server, job in server_jobs.items():
+    for server, job in list(server_jobs.items()):
         if not job.is_running():
             print('Server "%s" has exited prematurely.' % server)
 
diff --git a/tools/run_tests/run_performance_tests.py b/tools/run_tests/run_performance_tests.py
index 0a9d9663f0d..863db8dd468 100755
--- a/tools/run_tests/run_performance_tests.py
+++ b/tools/run_tests/run_performance_tests.py
@@ -253,7 +253,7 @@ def prepare_remote_hosts(hosts, prepare_local=False):
 
 
 def build_on_remote_hosts(hosts,
-                          languages=scenario_config.LANGUAGES.keys(),
+                          languages=list(scenario_config.LANGUAGES.keys()),
                           build_local=False):
     """Builds performance worker on remote hosts (and maybe also locally)."""
     build_timeout = 45 * 60
@@ -355,7 +355,8 @@ def create_scenarios(languages,
                      server_cpu_load=0):
     """Create jobspecs for scenarios to run."""
     all_workers = [
-        worker for workers in workers_by_lang.values() for worker in workers
+        worker for workers in list(workers_by_lang.values())
+        for worker in workers
     ]
     scenarios = []
     _NO_WORKERS = []
diff --git a/tools/run_tests/run_xds_tests.py b/tools/run_tests/run_xds_tests.py
index 0c145bf8813..87d4a398eea 100755
--- a/tools/run_tests/run_xds_tests.py
+++ b/tools/run_tests/run_xds_tests.py
@@ -129,10 +129,10 @@ def parse_test_cases(arg):
 def parse_port_range(port_arg):
     try:
         port = int(port_arg)
-        return range(port, port + 1)
+        return list(range(port, port + 1))
     except:
         port_min, port_max = port_arg.split(':')
-        return range(int(port_min), int(port_max) + 1)
+        return list(range(int(port_min), int(port_max) + 1))
 
 
 argp = argparse.ArgumentParser(description='Run xDS interop tests on GCP')
@@ -614,7 +614,7 @@ def compare_expected_instances(stats, expected_instances):
     Returns:
       Returns true if the instances are expected. False if not.
     """
-    for rpc_type, expected_peers in expected_instances.items():
+    for rpc_type, expected_peers in list(expected_instances.items()):
         rpcs_by_peer_for_type = stats.rpcs_by_method[rpc_type]
         rpcs_by_peer = rpcs_by_peer_for_type.rpcs_by_peer if rpcs_by_peer_for_type else None
         logger.debug('rpc: %s, by_peer: %s', rpc_type, rpcs_by_peer)
@@ -1031,7 +1031,7 @@ def test_metadata_filter(gcp, original_backend_service, instance_group,
         with open(bootstrap_path) as f:
             md = json.load(f)['node']['metadata']
             match_labels = []
-            for k, v in md.items():
+            for k, v in list(md.items()):
                 match_labels.append({'name': k, 'value': v})
 
         not_match_labels = [{'name': 'fake', 'value': 'fail'}]
@@ -2027,7 +2027,7 @@ def test_timeout(gcp, original_backend_service, instance_group):
                 after_stats = get_client_accumulated_stats()
 
                 success = True
-                for rpc, status in expected_results.items():
+                for rpc, status in list(expected_results.items()):
                     qty = (after_stats.stats_per_method[rpc].result[status] -
                            before_stats.stats_per_method[rpc].result[status])
                     want = test_runtime_secs * args.qps
@@ -2209,7 +2209,7 @@ def test_fault_injection(gcp, original_backend_service, instance_group):
                 after_stats = get_client_accumulated_stats()
 
                 success = True
-                for status, pct in expected_results.items():
+                for status, pct in list(expected_results.items()):
                     rpc = 'UNARY_CALL'
                     qty = (after_stats.stats_per_method[rpc].result[status] -
                            before_stats.stats_per_method[rpc].result[status])
@@ -2416,7 +2416,8 @@ def is_primary_instance_group(gcp, instance_group):
     # the client's actual locality.
     instance_names = get_instance_names(gcp, instance_group)
     stats = get_client_stats(_NUM_TEST_RPCS, _WAIT_FOR_STATS_SEC)
-    return all(peer in instance_names for peer in stats.rpcs_by_peer.keys())
+    return all(
+        peer in instance_names for peer in list(stats.rpcs_by_peer.keys()))
 
 
 def get_startup_script(path_to_server_binary, service_port):
@@ -3006,7 +3007,7 @@ def patch_url_map_backend_service(gcp,
         'weightedBackendServices': [{
             'backendService': service.url,
             'weight': w,
-        } for service, w in services_with_weights.items()]
+        } for service, w in list(services_with_weights.items())]
     } if services_with_weights else None
 
     config = {
diff --git a/tools/run_tests/sanity/check_bazel_workspace.py b/tools/run_tests/sanity/check_bazel_workspace.py
index 57e3da57b6b..f6dc0be391e 100755
--- a/tools/run_tests/sanity/check_bazel_workspace.py
+++ b/tools/run_tests/sanity/check_bazel_workspace.py
@@ -165,10 +165,10 @@ if len(workspace_git_hashes - git_submodule_hashes) > 0:
     print(
         "Found discrepancies between git submodules and Bazel WORKSPACE dependencies"
     )
-    print("workspace_git_hashes: %s" % workspace_git_hashes)
-    print("git_submodule_hashes: %s" % git_submodule_hashes)
-    print("workspace_git_hashes - git_submodule_hashes: %s" %
-          (workspace_git_hashes - git_submodule_hashes))
+    print(("workspace_git_hashes: %s" % workspace_git_hashes))
+    print(("git_submodule_hashes: %s" % git_submodule_hashes))
+    print(("workspace_git_hashes - git_submodule_hashes: %s" %
+           (workspace_git_hashes - git_submodule_hashes)))
     sys.exit(1)
 
 # Also check that we can override each dependency
diff --git a/tools/run_tests/sanity/check_deprecated_grpc++.py b/tools/run_tests/sanity/check_deprecated_grpc++.py
index 64e2080d53f..17bffc5fb85 100755
--- a/tools/run_tests/sanity/check_deprecated_grpc++.py
+++ b/tools/run_tests/sanity/check_deprecated_grpc++.py
@@ -134,9 +134,9 @@ if path_files.sort() != expected_files.sort():
     diff_plus = [file for file in path_files if file not in expected_files]
     diff_minus = [file for file in expected_files if file not in path_files]
     for file in diff_minus:
-        print('- ', file)
+        print(('- ', file))
     for file in diff_plus:
-        print('+ ', file)
+        print(('+ ', file))
     errors += 1
 
 if errors > 0:
@@ -161,7 +161,7 @@ for path_file in expected_files:
         fo.write(expected_content)
 
     if 0 != os.system('diff %s %s' % (path_file_expected, path_file)):
-        print('Difference found in file:', path_file)
+        print(('Difference found in file:', path_file))
         errors += 1
 
     os.remove(path_file_expected)
@@ -177,9 +177,9 @@ for root, dirs, files in os.walk('src'):
                     with open(path_file, "r") as fi:
                         content = fi.read()
                         if '#include <grpc++/' in content:
-                            print(
+                            print((
                                 'Failed: invalid include of deprecated headers in include/grpc++ in %s'
-                                % path_file)
+                                % path_file))
                             errors += 1
                 except IOError:
                     pass
diff --git a/tools/run_tests/sanity/check_qps_scenario_changes.py b/tools/run_tests/sanity/check_qps_scenario_changes.py
index fd5a12d9fb0..ce3de84e05d 100755
--- a/tools/run_tests/sanity/check_qps_scenario_changes.py
+++ b/tools/run_tests/sanity/check_qps_scenario_changes.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 # Copyright 2018 gRPC authors.
 #
@@ -23,7 +23,7 @@ subprocess.check_call(['./json_run_localhost_scenario_gen.py'])
 subprocess.check_call(['./qps_json_driver_scenario_gen.py'])
 subprocess.check_call(['buildifier', '-v', '-r', '.'])
 
-output = subprocess.check_output(['git', 'status', '--porcelain'])
+output = subprocess.check_output(['git', 'status', '--porcelain']).decode()
 qps_json_driver_bzl = 'test/cpp/qps/qps_json_driver_scenarios.bzl'
 json_run_localhost_bzl = 'test/cpp/qps/json_run_localhost_scenarios.bzl'
 
diff --git a/tools/run_tests/sanity/check_tracer_sanity.py b/tools/run_tests/sanity/check_tracer_sanity.py
index 0e1285c8581..040e0852e23 100755
--- a/tools/run_tests/sanity/check_tracer_sanity.py
+++ b/tools/run_tests/sanity/check_tracer_sanity.py
@@ -38,9 +38,9 @@ with open('doc/environment_variables.md') as f:
 
 for t in tracers:
     if t not in text:
-        print(
+        print((
             "ERROR: tracer \"%s\" is not mentioned in doc/environment_variables.md"
-            % t)
+            % t))
         errors += 1
 
 assert errors == 0
diff --git a/tools/run_tests/sanity/check_version.py b/tools/run_tests/sanity/check_version.py
index f7d6d277bd0..0afd00d138c 100755
--- a/tools/run_tests/sanity/check_version.py
+++ b/tools/run_tests/sanity/check_version.py
@@ -31,7 +31,7 @@ from expand_version import Version
 
 try:
     branch_name = subprocess.check_output('git rev-parse --abbrev-ref HEAD',
-                                          shell=True)
+                                          shell=True).decode()
 except:
     print('WARNING: not a git repository')
     branch_name = None
@@ -63,22 +63,22 @@ settings = build_yaml['settings']
 top_version = Version(settings['version'])
 if not check_version(top_version):
     errors += 1
-    print(warning % ('version', top_version))
+    print((warning % ('version', top_version)))
 
-for tag, value in settings.items():
+for tag, value in list(settings.items()):
     if re.match(r'^[a-z]+_version$', tag):
         value = Version(value)
         if tag != 'core_version':
             if value.major != top_version.major:
                 errors += 1
-                print('major version mismatch on %s: %d vs %d' %
-                      (tag, value.major, top_version.major))
+                print(('major version mismatch on %s: %d vs %d' %
+                       (tag, value.major, top_version.major)))
             if value.minor != top_version.minor:
                 errors += 1
-                print('minor version mismatch on %s: %d vs %d' %
-                      (tag, value.minor, top_version.minor))
+                print(('minor version mismatch on %s: %d vs %d' %
+                       (tag, value.minor, top_version.minor)))
         if not check_version(value):
             errors += 1
-            print(warning % (tag, value))
+            print((warning % (tag, value)))
 
 sys.exit(errors)
diff --git a/tools/run_tests/sanity/core_banned_functions.py b/tools/run_tests/sanity/core_banned_functions.py
index c88db699cf8..1d751d8f715 100755
--- a/tools/run_tests/sanity/core_banned_functions.py
+++ b/tools/run_tests/sanity/core_banned_functions.py
@@ -66,11 +66,11 @@ for root, dirs, files in os.walk('src/core'):
             continue
         with open(path) as f:
             text = f.read()
-        for banned, exceptions in BANNED_EXCEPT.items():
+        for banned, exceptions in list(BANNED_EXCEPT.items()):
             if path in exceptions:
                 continue
             if banned in text:
-                print('Illegal use of "%s" in %s' % (banned, path))
+                print(('Illegal use of "%s" in %s' % (banned, path)))
                 errors += 1
 
 assert errors == 0
diff --git a/tools/run_tests/task_runner.py b/tools/run_tests/task_runner.py
index d54a5c5ea83..44bf6ab823a 100755
--- a/tools/run_tests/task_runner.py
+++ b/tools/run_tests/task_runner.py
@@ -35,7 +35,7 @@ _TARGETS += package_targets.targets()
 def _create_build_map():
     """Maps task names and labels to list of tasks to be built."""
     target_build_map = dict([(target.name, [target]) for target in _TARGETS])
-    if len(_TARGETS) > len(target_build_map.keys()):
+    if len(_TARGETS) > len(list(target_build_map.keys())):
         raise Exception('Target names need to be unique')
 
     label_build_map = {}
@@ -47,7 +47,7 @@ def _create_build_map():
             else:
                 label_build_map[label] = [target]
 
-    if set(target_build_map.keys()).intersection(label_build_map.keys()):
+    if set(target_build_map.keys()).intersection(list(label_build_map.keys())):
         raise Exception('Target names need to be distinct from label names')
     return dict(list(target_build_map.items()) + list(label_build_map.items()))