Handle KeyboardInterrupt consistently in python scripts

git_footers.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.
 
 import argparse
 import re
 import sys
 
 from collections import defaultdict
@@ skipping 121 matching lines @@
   elif opts.position_ref:
     print get_position(footers)[0]
   elif opts.position_num:
     pos = get_position(footers)
     assert pos[1], 'No valid position for commit'
     print pos[1]
   else:
     for k in footers.keys():
       for v in footers[k]:
         print '%s: %s' % (k, v)
+  return 0
 
 
 if __name__ == '__main__':
-  sys.exit(main(sys.argv[1:]))
+  try:
+    sys.exit(main(sys.argv[1:]))
+  except KeyboardInterrupt:
+    sys.stderr.write('interrupted\n')
+    sys.exit(1)