[Python grpcio_tools] Update version requirement of protobuf in grpcio_tools (#36230)

Since we already finished v26.1 upgrade in https://github.com/grpc/grpc/pull/35796
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Closes #36230

PiperOrigin-RevId: 623960260

requirements.txt

@@ -1,5 +1,5 @@
 # GRPC Python setup requirements
 coverage>=4.0
 cython>=3.0.0
-protobuf>=4.21.3,<5.0dev
+protobuf>=5.26.1,<6.0dev
 wheel>=0.29

src/python/grpcio_channelz/setup.py

@@ -61,7 +61,7 @@ PACKAGE_DIRECTORIES = {
 }
 
 INSTALL_REQUIRES = (
-    "protobuf>=4.21.6",
+    "protobuf>=5.26.1,<6.0dev",
     "grpcio>={version}".format(version=grpc_version.VERSION),
 )
 

src/python/grpcio_csds/setup.py

@@ -39,7 +39,7 @@ PACKAGE_DIRECTORIES = {
 }
 
 INSTALL_REQUIRES = (
-    "protobuf>=4.21.6",
+    "protobuf>=5.26.1,<6.0dev",
     f"xds-protos=={grpc_version.VERSION}",
     f"grpcio>={grpc_version.VERSION}",
 )

src/python/grpcio_health_checking/setup.py

@@ -60,7 +60,7 @@ PACKAGE_DIRECTORIES = {
 }
 
 INSTALL_REQUIRES = (
-    "protobuf>=4.21.6",
+    "protobuf>=5.26.1,<6.0dev",
     "grpcio>={version}".format(version=grpc_version.VERSION),
 )
 

src/python/grpcio_reflection/setup.py

@@ -61,7 +61,7 @@ PACKAGE_DIRECTORIES = {
 }
 
 INSTALL_REQUIRES = (
-    "protobuf>=4.21.6",
+    "protobuf>=5.26.1,<6.0dev",
     "grpcio>={version}".format(version=grpc_version.VERSION),
 )
 

src/python/grpcio_status/setup.py

@@ -60,7 +60,7 @@ PACKAGE_DIRECTORIES = {
 }
 
 INSTALL_REQUIRES = (
-    "protobuf>=4.21.6",
+    "protobuf>=5.26.1,<6.0dev",
     "grpcio>={version}".format(version=grpc_version.VERSION),
     "googleapis-common-protos>=1.5.5",
 )

src/python/grpcio_testing/setup.py

@@ -49,7 +49,7 @@ PACKAGE_DIRECTORIES = {
 }
 
 INSTALL_REQUIRES = (
-    "protobuf>=4.21.6",
+    "protobuf>=5.26.1,<6.0dev",
     "grpcio>={version}".format(version=grpc_version.VERSION),
 )
 

src/python/grpcio_tests/setup.py

@@ -46,7 +46,7 @@ INSTALL_REQUIRES = (
     "grpcio-observability>={version}".format(version=grpc_version.VERSION),
     "xds-protos>={version}".format(version=grpc_version.VERSION),
     "oauth2client>=1.4.7",
-    "protobuf>=4.21.6rc1,!=4.22.0.*",
+    "protobuf>=5.26.1,<6.0dev",
     "google-auth>=1.17.2",
     "requests>=2.14.2",
     "absl-py>=1.4.0",

tools/distrib/python/grpcio_tools/setup.py

@@ -329,7 +329,7 @@ setuptools.setup(
     packages=setuptools.find_packages("."),
     python_requires=">=3.8",
     install_requires=[
-        "protobuf>=4.21.6,<5.0dev",
+        "protobuf>=5.26.1,<6.0dev",
         "grpcio>={version}".format(version=grpc_version.VERSION),
         "setuptools",
     ],

tools/distrib/python/xds_protos/setup.py

@@ -39,7 +39,7 @@ CLASSIFIERS = [
 ]
 INSTALL_REQUIRES = [
     "grpcio>=1.49.0",
-    "protobuf>=4.21.6,<5.0dev",
+    "protobuf>=5.26.1,<6.0dev",
 ]
 
 SETUP_REQUIRES = INSTALL_REQUIRES + ["grpcio-tools>=1.49.0"]