def METHOD_NAME(proto_ver):
    if proto_ver == 4:
        bridge_protocol = "mqttv311"
        proto_ver_connect = 128+4
    else:
        bridge_protocol = "mqttv50"
        proto_ver_connect = 5
    (port1, port2) = mosq_test.get_port(2)
    conf_file = os.path.basename(__file__).replace('.py', '.conf')
    write_config(conf_file, port1, port2, bridge_protocol)
    rc = 1
    keepalive = 60
    client_id = socket.gethostname()+".bridge_sample"
    connect_packet = mosq_test.gen_connect(client_id, keepalive=keepalive, clean_session=False, proto_ver=proto_ver_connect)
    connack_packet = mosq_test.gen_connack(rc=0, proto_ver=proto_ver)
    if proto_ver == 5:
        opts = mqtt5_opts.MQTT_SUB_OPT_NO_LOCAL | mqtt5_opts.MQTT_SUB_OPT_RETAIN_AS_PUBLISHED
    else:
        opts = 0
    mid = 1
    subscribe_packet = mosq_test.gen_subscribe(mid, "bridge/#", 1 | opts, proto_ver=proto_ver)
    suback_packet = mosq_test.gen_suback(mid, 1, proto_ver=proto_ver)
    mid = 2
    subscribe2_packet = mosq_test.gen_subscribe(mid, "bridge/#", 1 | opts, proto_ver=proto_ver)
    suback2_packet = mosq_test.gen_suback(mid, 1, proto_ver=proto_ver)
    mid = 3
    publish_packet = mosq_test.gen_publish("bridge/disconnect/test", qos=1, mid=mid, payload="disconnect-message", proto_ver=proto_ver)
    publish_dup_packet = mosq_test.gen_publish("bridge/disconnect/test", qos=1, mid=mid, payload="disconnect-message", dup=True, proto_ver=proto_ver)
    puback_packet = mosq_test.gen_puback(mid, proto_ver=proto_ver)
    mid = 20
    publish2_packet = mosq_test.gen_publish("bridge/disconnect/test", qos=1, mid=mid, payload="disconnect-message", proto_ver=proto_ver)
    puback2_packet = mosq_test.gen_puback(mid, proto_ver=proto_ver)
    ssock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    ssock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    ssock.settimeout(40)
    ssock.bind(('', port1))
    ssock.listen(5)
    try:
        broker = mosq_test.start_broker(filename=os.path.basename(__file__), port=port2, use_conf=True)
        (bridge, address) = ssock.accept()
        bridge.settimeout(20)
        mosq_test.expect_packet(bridge, "connect", connect_packet)
        bridge.send(connack_packet)
        mosq_test.expect_packet(bridge, "subscribe", subscribe_packet)
        bridge.send(suback_packet)
        bridge.send(publish_packet)
        # Bridge doesn't have time to respond but should expect us to retry
        # and so remove PUBACK.
        bridge.close()
        (bridge, address) = ssock.accept()
        bridge.settimeout(20)
        mosq_test.expect_packet(bridge, "connect", connect_packet)
        bridge.send(connack_packet)
        mosq_test.expect_packet(bridge, "2nd subscribe", subscribe2_packet)
        bridge.send(suback2_packet)
        # Send a different publish message to make sure the response isn't to the old one.
        bridge.send(publish2_packet)
        mosq_test.expect_packet(bridge, "puback", puback2_packet)
        rc = 0
        bridge.close()
    except mosq_test.TestError:
        pass
    finally:
        os.remove(conf_file)
        try:
            bridge.close()
        except NameError:
            pass
        broker.terminate()
        broker.wait()
        (stdo, stde) = broker.communicate()
        ssock.close()
        if rc:
            print(stde.decode('utf-8'))
            exit(rc)