docs: def astimezone(self, tzinfo):
      """Returns a version of this timestamp converted to the given timezone.
  
      Args:
        tzinfo: Either a datetime.tzinfo object or a string (which will be looked
                up in pytz.
  
      Returns:
        A datetime_tz object in the given timezone.
      """
      # Assert we are not a naive datetime object
      assert self.tzinfo is not None
  
      tzinfo = _tzinfome(tzinfo)
  
      d = self.asdatetime(naive=False).astimezone(tzinfo)
      return type(self)(d)