Merge pull request #1273 from soltanmm/auth-interop

Fix Python auth and interop test
diff --git a/src/python/interop/interop/client.py b/src/python/interop/interop/client.py
index bae5e17..41f0d94 100644
--- a/src/python/interop/interop/client.py
+++ b/src/python/interop/interop/client.py
@@ -64,7 +64,7 @@
   return parser.parse_args()
 
 def _oauth_access_token(args):
-  credentials = client.GoogleCredentials.get_application_default()
+  credentials = oauth2client_client.GoogleCredentials.get_application_default()
   scoped_credentials = credentials.create_scoped([args.oauth_scope])
   return scoped_credentials.get_access_token().access_token
 
diff --git a/src/python/interop/interop/methods.py b/src/python/interop/interop/methods.py
index c69771d..909b738 100644
--- a/src/python/interop/interop/methods.py
+++ b/src/python/interop/interop/methods.py
@@ -292,7 +292,7 @@
   if wanted_email != response.username:
     raise ValueError(
         'expected username %s, got %s' % (wanted_email, response.username))
-  if response.oauth_scope in args.oauth_scope:
+  if args.oauth_scope.find(response.oauth_scope) == -1:
     raise ValueError(
         'expected to find oauth scope "%s" in received "%s"' %
             (response.oauth_scope, args.oauth_scope))
diff --git a/src/python/src/grpc/early_adopter/implementations.py b/src/python/src/grpc/early_adopter/implementations.py
index 35456d3..f3f2a04 100644
--- a/src/python/src/grpc/early_adopter/implementations.py
+++ b/src/python/src/grpc/early_adopter/implementations.py
@@ -223,7 +223,8 @@
   breakdown = _face_utilities.break_down_invocation(service_name, methods)
   return _Stub(
       breakdown, host, port, secure, root_certificates, private_key,
-      certificate_chain, server_host_override=server_host_override)
+      certificate_chain, server_host_override=server_host_override,
+      metadata_transformer=metadata_transformer)
 
 
 def server(