Merge pull request #650 from Yhg1s/master

src/python/src/grpc/_adapter/_c.c

src/python/src/grpc/_adapter/_call.c

src/python/src/grpc/_adapter/_channel.c

src/python/src/grpc/_adapter/_completion_queue.c

src/python/src/grpc/_adapter/_server.c

src/python/src/grpc/_adapter/_server_credentials.c