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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_timeout_for_leave(self, timeout, datapath, dst, in_port):
 """the process when the QUERY from the switch timeout expired."""

        parser = datapath.ofproto_parser
        dpid = datapath.id

        hub.sleep(timeout)
        outport = self._to_querier[dpid]['port']

        if self._to_hosts[dpid][dst]['ports'][in_port]['out']:
            return

        del self._to_hosts[dpid][dst]['ports'][in_port]
        self._del_flow_entry(datapath, in_port, dst)
        actions = []
        ports = []
        for port in self._to_hosts[dpid][dst]['ports']:
            actions.append(parser.OFPActionOutput(port))
            ports.append(port)

        if len(actions):
            self._send_event(
                EventMulticastGroupStateChanged(
                    MG_MEMBER_CHANGED, dst, outport, ports))
            self._set_flow_entry(
                datapath, actions, outport, dst)
            self._to_hosts[dpid][dst]['leave'] = None
        else:
            self._remove_multicast_group(datapath, outport, dst)
            del self._to_hosts[dpid][dst]