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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _send_ack(self, ip, port, packet, update_timestamp=True):
 """ Send an ack packet :param ip: Ip to send to :type ip: str :param port: Port to send to :type port: int :param packet: Packet to be acknowledged :type packet: APPMessage :param update_timestamp: Should update timestamp to current :type update_timestamp: bool :rtype: None """

        # TODO: maybe wait a bit, so the ack could get attached to another
        # packet
        ack = APPMessage(message_type=MsgType.ACK)
        ack.header.ack_sequence_number = packet.header.sequence_number
        self._send_packet(
            ip, port, ack,
            update_timestamp=update_timestamp, acknowledge_packet=False
        )