geeknam/python-gcm — pull request #30 by imankulov (2013-03-20 14:55:02+00:00)
Title: Remove GCMNoCollapseKeyException

It turned out that collapse key is not a requirement for messages with
TTL at least since Oct, 2012.

See https://plus.google.com/u/0/104524825852741167674/posts/AEpCusdNZY9
for details.