datetime.datetime.utcfromtimestamp(1322745926.123)
returns datetime.datetime(2011, 12, 1, 13, 25, 26, 123000)
which is in the UTC timezone. With:
a = pytz.utc.localize(datetime.datetime.utcfromtimestamp(1322745926.123))
you get a timezone-aware datetime object which can be then converted to any timezone you need:
a == datetime.datetime(2011, 12, 1, 13, 25, 26, 123000, tzinfo=<UTC>)
a.astimezone(pytz.timezone('Europe/Paris'))
# datetime.datetime(2011, 12, 1, 14, 25, 26, 123000, tzinfo=<DstTzInfo 'Europe/Paris' CET+1:00:00 STD>)