diff --git a/src/python/grpcio/commands.py b/src/python/grpcio/commands.py
index 5b21daaf444..8240beb2958 100644
--- a/src/python/grpcio/commands.py
+++ b/src/python/grpcio/commands.py
@@ -101,7 +101,7 @@ class SphinxDocumentation(setuptools.Command):
         target_dir = os.path.join(GRPC_STEM, 'doc', 'build')
         exit_code = sphinx.cmd.build.build_main(
             ['-b', 'html', '-W', '--keep-going', source_dir, target_dir])
-        if exit_code is not 0:
+        if exit_code != 0:
             raise CommandError(
                 "Documentation generation has warnings or errors")