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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 _do_leave(self, leave, in_port, msg):
 """the process when the snooper received a LEAVE message."""

        datapath = msg.datapath
        dpid = datapath.id
        ofproto = datapath.ofproto
        parser = datapath.ofproto_parser

        # check whether the querier port has been specified.
        if not self._to_querier.get(dpid):
            self.logger.info("no querier exists.")
            return

        # save this LEAVE message and reset the condition of the port
        # that received this message.
        self._to_hosts.setdefault(dpid, {})
        self._to_hosts[dpid].setdefault(
            leave.address,
            {'replied': False, 'leave': None, 'ports': {}})
        self._to_hosts[dpid][leave.address]['leave'] = msg
        self._to_hosts[dpid][leave.address]['ports'][in_port] = {
            'out': False, 'in': False}

        # create a specific query.
        timeout = igmp.LAST_MEMBER_QUERY_INTERVAL
        res_igmp = igmp.igmp(
            msgtype=igmp.IGMP_TYPE_QUERY,
            maxresp=timeout * 10,
            csum=0,
            address=leave.address)
        res_ipv4 = ipv4.ipv4(
            total_length=len(ipv4.ipv4()) + len(res_igmp),
            proto=inet.IPPROTO_IGMP, ttl=1,
            src=self._to_querier[dpid]['ip'],
            dst=igmp.MULTICAST_IP_ALL_HOST)
        res_ether = ethernet.ethernet(
            dst=igmp.MULTICAST_MAC_ALL_HOST,
            src=self._to_querier[dpid]['mac'],
            ethertype=ether.ETH_TYPE_IP)
        res_pkt = packet.Packet()
        res_pkt.add_protocol(res_ether)
        res_pkt.add_protocol(res_ipv4)
        res_pkt.add_protocol(res_igmp)
        res_pkt.serialize()

        # send a specific query to the host that sent this message.
        actions = [parser.OFPActionOutput(ofproto.OFPP_IN_PORT)]
        self._do_packet_out(datapath, res_pkt.data, in_port, actions)

        # wait for REPORT messages.
        hub.spawn(self._do_timeout_for_leave, timeout, datapath,
                  leave.address, in_port)