How to use the gmqtt.Subscription function in gmqtt

async def test_basic_subscriptions(init_clients):
    aclient, callback, bclient, callback2 = init_clients

    await aclient.connect(host=host, port=port)
    await bclient.connect(host=host, port=port)

    subscriptions = [
        gmqtt.Subscription(TOPICS[1], qos=1),
        gmqtt.Subscription(TOPICS[2], qos=2),
    ]
    bclient.subscribe(subscriptions, user_property=('key', 'value'), subscription_identifier=1)

    bclient.subscribe(gmqtt.Subscription(TOPICS[3], qos=1), user_property=('key', 'value'), subscription_identifier=2)
    await asyncio.sleep(1)

    aclient.publish(TOPICS[3], b"qos 0")
    aclient.publish(TOPICS[1], b"qos 1", 1)
    aclient.publish(TOPICS[2], b"qos 2", 2)
    await asyncio.sleep(1)
    assert len(callback2.messages) == 3

async def test_basic_subscriptions(init_clients):
    aclient, callback, bclient, callback2 = init_clients

    await aclient.connect(host=host, port=port)
    await bclient.connect(host=host, port=port)

    subscriptions = [
        gmqtt.Subscription(TOPICS[1], qos=1),
        gmqtt.Subscription(TOPICS[2], qos=2),
    ]
    bclient.subscribe(subscriptions, user_property=('key', 'value'), subscription_identifier=1)

    bclient.subscribe(gmqtt.Subscription(TOPICS[3], qos=1), user_property=('key', 'value'), subscription_identifier=2)
    await asyncio.sleep(1)

    aclient.publish(TOPICS[3], b"qos 0")
    aclient.publish(TOPICS[1], b"qos 1", 1)
    aclient.publish(TOPICS[2], b"qos 2", 2)
    await asyncio.sleep(1)
    assert len(callback2.messages) == 3

async def test_basic_subscriptions(init_clients):
    aclient, callback, bclient, callback2 = init_clients

    await aclient.connect(host=host, port=port)
    await bclient.connect(host=host, port=port)

    subscriptions = [
        gmqtt.Subscription(TOPICS[1], qos=1),
        gmqtt.Subscription(TOPICS[2], qos=2),
    ]
    bclient.subscribe(subscriptions, user_property=('key', 'value'), subscription_identifier=1)

    bclient.subscribe(gmqtt.Subscription(TOPICS[3], qos=1), user_property=('key', 'value'), subscription_identifier=2)
    await asyncio.sleep(1)

    aclient.publish(TOPICS[3], b"qos 0")
    aclient.publish(TOPICS[1], b"qos 1", 1)
    aclient.publish(TOPICS[2], b"qos 2", 2)
    await asyncio.sleep(1)
    assert len(callback2.messages) == 3

async def main(broker_host, broker_port, token):
    # create client instance, kwargs (session expiry interval and maximum packet size)
    # will be send as properties in connect packet
    sub_client = gmqtt.Client("clientgonnasub", session_expiry_interval=600, maximum_packet_size=65535)

    assign_callbacks_to_client(sub_client)
    sub_client.set_auth_credentials(token, None)
    await sub_client.connect(broker_host, broker_port)

    # two overlapping subscriptions with different subscription identifiers
    sub_client.subscribe('TEST/PROPS/#', qos=1, subscription_identifier=1)
    sub_client.subscribe([gmqtt.Subscription('TEST/+', qos=1), gmqtt.Subscription('TEST', qos=0)],
                         subscription_identifier=2)

    pub_client = gmqtt.Client("clientgonnapub")

    assign_callbacks_to_client(pub_client)
    pub_client.set_auth_credentials(token, None)
    await pub_client.connect(broker_host, broker_port)

    # this message received by sub_client will have two subscription identifiers
    pub_client.publish('TEST/PROPS/42', '42 is the answer', qos=1, content_type='utf-8',
                       message_expiry_interval=60, user_property=('time', str(time.time())))

    pub_client.publish('TEST', 'Test 42', qos=1, content_type='utf-8',
                       message_expiry_interval=60, user_property=('time', str(time.time())))

    # just another way to publish same message