Handle KeyboardInterrupt consistently in python scripts

git_try.py

 #!/usr/bin/python
 # Copyright (c) 2011 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.
 """Wrapper for trychange.py for git checkout."""
 
 import logging
 import sys
 
 import breakpad  # pylint: disable=W0611
@@ skipping 23 matching lines @@
     return None
 
 
 def GetRietveldServerUrl():
   try:
     return GIT.Capture(['config', 'rietveld.server'], '.').strip()
   except subprocess2.CalledProcessError:
     return None
 
 
-if __name__ == '__main__':
-  args = sys.argv[1:]
+def main(args):
   patchset = GetRietveldPatchsetNumber()
   if patchset:
     args.extend([
         '--issue', GetRietveldIssueNumber(),
         '--patchset', patchset,
     ])
   else:
     rietveld_url = GetRietveldServerUrl()
     if rietveld_url:
       args.extend(['--rietveld_url', GetRietveldServerUrl()])
   try:
     cl = git_cl.Changelist()
     change = cl.GetChange(cl.GetUpstreamBranch(), None)
     # Hack around a limitation in logging.
     logging.getLogger().handlers = []
     sys.exit(trychange.TryChange(
         args, change, swallow_exception=False,
         prog='git try',
         extra_epilog='\n'
                      'git try will diff against your tracked branch and will '
                      'detect your rietveld\n'
                      'code review if you are using git-cl\n'))
   except third_party.upload.ClientLoginError, e:
     print('Got an exception while trying to log in to Rietveld.')
     print(str(e))
+  return 0
+
+
+if __name__ == '__main__':
+  try:
+    sys.exit(main(sys.argv[1:]))
+  except KeyboardInterrupt:
+    sys.stderr.write('interrupted\n')
+    sys.exit(1)