I don't think there is anything we can do here.  Without a TZ database, Python has to rely on time.tzname which in case of TZ=Europe/Moscow returns

>>> time.tzname
('MSK', 'MSK')

Hardcoding a timezones dictionary as done in email module may work for a handful of American timezones, but will not work for TZ's like Europe/Moscow.

$ zdump -v  Europe/Moscow| tail
Europe/Moscow  Sat Oct 24 22:59:59 2009 UTC = Sun Oct 25 02:59:59 2009 MSD isdst=1
Europe/Moscow  Sat Oct 24 23:00:00 2009 UTC = Sun Oct 25 02:00:00 2009 MSK isdst=0
Europe/Moscow  Sat Mar 27 22:59:59 2010 UTC = Sun Mar 28 01:59:59 2010 MSK isdst=0
Europe/Moscow  Sat Mar 27 23:00:00 2010 UTC = Sun Mar 28 03:00:00 2010 MSD isdst=1
Europe/Moscow  Sat Oct 30 22:59:59 2010 UTC = Sun Oct 31 02:59:59 2010 MSD isdst=1
Europe/Moscow  Sat Oct 30 23:00:00 2010 UTC = Sun Oct 31 02:00:00 2010 MSK isdst=0
Europe/Moscow  Sat Mar 26 22:59:59 2011 UTC = Sun Mar 27 01:59:59 2011 MSK isdst=0
Europe/Moscow  Sat Mar 26 23:00:00 2011 UTC = Sun Mar 27 03:00:00 2011 MSK isdst=0
Europe/Moscow  Mon Jan 18 03:14:07 2038 UTC = Mon Jan 18 07:14:07 2038 MSK isdst=0
Europe/Moscow  Tue Jan 19 03:14:07 2038 UTC = Tue Jan 19 07:14:07 2038 MSK isdst=0

(And it looks like the planned for 2014-10-26 switch back to winter time is not in my laptop's database yet.)