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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 queue_context_entry(exchange, queue_name, routing=None):
 """ forms queue's context entry """

    if routing is None:
        routing = queue_name

    queue_entry = QueueContextEntry(mq_queue=queue_name,
                                    mq_exchange=exchange,
                                    mq_routing_key=routing)
    return queue_entry