def METHOD_NAME(self):
    # normal time zone that should have a zoneinfo file
    meeting = MeetingFactory(type_id='ietf', time_zone='America/Los_Angeles', populate_schedule=False)
    vtz = meeting.vtimezone()
    self.assertIsNotNone(vtz)
    self.assertGreater(len(vtz), 0)
    # time zone that does not have a zoneinfo file should return None
    meeting = MeetingFactory(type_id='ietf', time_zone='Fake/Time_Zone', populate_schedule=False)
    vtz = meeting.vtimezone()
    self.assertIsNone(vtz)
    # ioerror trying to read zoneinfo should return None
    meeting = MeetingFactory(type_id='ietf', time_zone='America/Los_Angeles', populate_schedule=False)
    with patch('ietf.meeting.models.io.open', side_effect=IOError):
        vtz = meeting.vtimezone()
    self.assertIsNone(vtz)