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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 _append_task(t):
 """Append a task to the queue. Expected argument is a tuple of the following form: (task class, args, kwargs, extra kwargs). This doesn't append to queue if the argument is already in the queue. """

    task_queue = _get_task_queue()
    if t not in task_queue:
        log.debug('Appended new task to the queue: %s.', t)
        task_queue.append(t)
    else:
        log.debug('Did not append duplicate task to the queue: %s.', t)
    return None