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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 _sync(pack):
 """Simulate a package travelling through the cluster."""

    task_queue = Queue()
    result_queue = Queue()
    task = SignedPackage.loads(pack)
    task_queue.put(task)
    task_queue.put('STOP')
    worker(task_queue, result_queue, Value('f', -1))
    result_queue.put('STOP')
    monitor(result_queue)
    task_queue.close()
    task_queue.join_thread()
    result_queue.close()
    result_queue.join_thread()
    return task['id']