Return a timestamp message.

        Returns:
            (:class:`~google.protobuf.timestamp_pb2.Timestamp`): Timestamp message

def timestamp_pb(self):
        """Return a timestamp message.

        Returns:
            (:class:`~google.protobuf.timestamp_pb2.Timestamp`): Timestamp message
        """
        inst = self if self.tzinfo is not None else self.replace(tzinfo=pytz.UTC)
        delta = inst - _UTC_EPOCH
        seconds = int(delta.total_seconds())
        nanos = self._nanosecond or self.microsecond * 1000
        return timestamp_pb2.Timestamp(seconds=seconds, nanos=nanos)