diff --git a/my_activity.py b/my_activity.py
index b4be6fd204..0904b2c0a9 100755
--- a/my_activity.py
+++ b/my_activity.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env vpython
+#!/usr/bin/env vpython3
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
@@ -46,6 +46,8 @@ import gerrit_util
 
 
 if sys.version_info.major == 2:
+  logging.warning(
+      'Python 2 is deprecated. Run my_activity.py using vpython3.')
   import urllib as urllib_parse
 else:
   import urllib.parse as urllib_parse