getpelican/pelican — pull request #1153 by talha131 (2013-11-09 20:48:13+00:00)
Title: Check argument type in get_date utility function before processing it

Sitemap plugin calls this method to convert `modified` metadate into
datetime. Depending on the version of Pelican `modified` can be string
or a datetime object.

Therefore get_date should check for the type of argument otherwise
Pelican fails with a critical error.