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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_callback(self, session, block_id, data):
 """ Queues up a callback event to occur for a session with the given payload data. Will block if the queue is full. :param session: the session with a defined callback function to call. :param block_id: the block_id of the message received. :param data: the data payload of the message received. """

        self._queue.put((session, block_id, data))