Don't send mail for policy_checklist comments.

util.py

 # Copyright (c) 2013 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.
 
 import collections
 import email.utils
 
 
 def lazy_property(func):
   """A decorator for lazy properties."""
@@ skipping 68 matching lines @@
 def get_emails(string):
   """Normalizes a string containing a list of email recepients.
 
   Takes a string in the format present in mail headers and returns a list of
   email addresses. For example, the input
       'test@example.com, committers <committers@chromium.org>
   will produce this return value:
       [ 'test@example.com', 'committers@chromium.org' ]
   """
   return [entry[1] for entry in email.utils.getaddresses([string])]
+
+
+def canonicalize_email(address):
+  """Takes an email address and returns its canonicalized form."""
+  emails = get_emails(address)
+  assert len(emails) == 1
+  return emails[0]