Handle KeyboardInterrupt consistently in python scripts

git_auto_svn.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 """Performs all git-svn setup steps necessary for 'git svn dcommit' to work.
 
 Assumes that trunk of the svn remote maps to master of the git remote.
 
 Example:
@@ skipping 37 matching lines @@
     raise subprocess2.CalledProcessError(retcode, cmd, os.getcwd(), ret, err)
 
   return ret, err
 
 
 def main(argv):
   # No command line flags. Just use the parser to prevent people from trying
   # to pass flags that don't do anything, and to provide 'usage'.
   parser = argparse.ArgumentParser(
       description='Automatically set up git-svn for a repo mirrored from svn.')
-  parser.parse_args(argv[1:])
+  parser.parse_args(argv)
 
   upstream = root()
   message = run_git('log', '-1', '--format=%B', upstream)
   footers = parse_footers(message)
   git_svn_id = get_unique(footers, 'git-svn-id')
   match = GIT_SVN_ID_PATTERN.match(git_svn_id)
   assert match, 'No valid git-svn-id footer found on %s.' % upstream
   print 'Found git-svn-id footer %s on %s' % (match.group(1), upstream)
 
   parsed_svn = urlparse.urlparse(match.group(1))
@@ skipping 19 matching lines @@
       continue
   assert svn_repo is not None, 'Unable to find svn repo for %s' % match.group(1)
   print 'Found upstream svn repo %s and path %s' % (svn_repo, svn_path)
 
   set_config('svn-remote.svn.url', svn_repo)
   set_config('svn-remote.svn.fetch',
              '%s:refs/remotes/%s' % (svn_path, upstream))
   print 'Configured metadata, running "git svn fetch". This may take some time.'
   for line in run_git_stream('svn', 'fetch').xreadlines():
     print line.strip()
+  return 0
 
 
 if __name__ == '__main__':
-  sys.exit(main(sys.argv))
+  try:
+    sys.exit(main(sys.argv[1:]))
+  except KeyboardInterrupt:
+    sys.stderr.write('interrupted\n')
+    sys.exit(1)