I know this is really old question, but you can do it with python datetime.strptime()
>>> from datetime import datetime
>>> date_format = "%Y-%m-%dT%H:%M:%S.%fZ"
>>> datetime.strptime('2008-09-26T01:51:42.000Z', date_format)
datetime.datetime(2008, 9, 26, 1, 51, 42)