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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 single_queue_send( transport: 'UDPTransport', recipient: Address, queue: Queue_T, queue_identifier: QueueIdentifier, event_stop: Event, event_healthy: Event, event_unhealthy: Event, message_retries: int, message_retry_timeout: int, message_retry_max_timeout: int, ):
 """ Handles a single message queue for `recipient`. Notes: - This task must be the only consumer of queue. - This task can be killed at any time, but the intended usage is to stop it with the event_stop. - If there are many queues for the same recipient, it is the caller's responsibility to not start them together to avoid congestion. - This task assumes the endpoint is never cleared after it's first known. If this assumption changes the code must be updated to handle unknown addresses. """


    # A NotifyingQueue is required to implement cancelability, otherwise the
    # task cannot be stopped while the greenlet waits for an element to be
    # inserted in the queue.
    if not isinstance(queue, NotifyingQueue):
        raise ValueError('queue must be a NotifyingQueue.')

    # Reusing the event, clear must be carefully done
    data_or_stop = event_first_of(
        queue,
        event_stop,
    )

    # Wait for the endpoint registration or to quit
    transport.log.debug(
        'queue: waiting for node to become healthy',
        queue_identifier=queue_identifier,
        queue_size=len(queue),
    )

    event_first_of(
        event_healthy,
        event_stop,
    ).wait()

    transport.log.debug(
        'queue: processing queue',
        queue_identifier=queue_identifier,
        queue_size=len(queue),
    )

    while True:
        data_or_stop.wait()

        if event_stop.is_set():
            transport.log.debug(
                'queue: stopping',
                queue_identifier=queue_identifier,
                queue_size=len(queue),
            )
            return

        # The queue is not empty at this point, so this won't raise Empty.
        # This task being the only consumer is a requirement.
        (messagedata, message_id) = queue.peek(block=False)

        transport.log.debug(
            'queue: sending message',
            recipient=pex(recipient),
            msgid=message_id,
            queue_identifier=queue_identifier,
            queue_size=len(queue),
        )

        backoff = timeout_exponential_backoff(
            message_retries,
            message_retry_timeout,
            message_retry_max_timeout,
        )

        acknowledged = retry_with_recovery(
            transport,
            messagedata,
            message_id,
            recipient,
            event_stop,
            event_healthy,
            event_unhealthy,
            backoff,
        )

        if acknowledged:
            queue.get()

            # Checking the length of the queue does not trigger a
            # context-switch, so it's safe to assume the length of the queue
            # won't change under our feet and when a new item will be added the
            # event will be set again.
            if not queue:
                data_or_stop.clear()

                if event_stop.is_set():
                    return