add compatibility check badge to README
diff --git a/src/python/grpcio/README.rst b/src/python/grpcio/README.rst
index 07c9434..c7c6aa4 100644
--- a/src/python/grpcio/README.rst
+++ b/src/python/grpcio/README.rst
@@ -1,8 +1,13 @@
 gRPC Python
 ===========
 
+|compat_check_pypi|
+
 Package for gRPC Python.
 
+.. |compat_check_pypi| image:: https://python-compatibility-tools.appspot.com/one_badge_image?package=grpcio
+   :target: https://python-compatibility-tools.appspot.com/one_badge_target?package=grpcio
+
 Supported Python Versions
 -------------------------
 Python >= 3.5