code: def timezone(haystack_tz, version=LATEST_VER):
      
      tz_map = get_tz_map(version=version)
      try:
          tz_name = tz_map[haystack_tz]
      except KeyError:
          raise ValueError('%s is not a recognised timezone on this host' \
                  % haystack_tz)
      return pytz.timezone(tz_name)
docs: Retrieve the Haystack timezone