To get a set of all valid timezone names (ids) from the tz database, you could use pytz
module in Python:
>>> import pytz # $ pip install pytz
>>> pytz.all_timezones_set
LazySet({'Africa/Abidjan',
'Africa/Accra',
'Africa/Addis_Ababa',
'Africa/Algiers',
'Africa/Asmara',
'Africa/Asmera',
...
'UTC',
'Universal',
'W-SU',
'WET',
'Zulu'})