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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 get_subscriber_queue(self, event_types=None):
 """Create a new queue for a specific combination of event types and return it. Returns: a :class:`multiprocessing.Queue`. Raises: RuntimeError if called after `run` """


        try:
            self.started_queue.get(timeout=1)
            raise RuntimeError('Cannot create a new subscriber queue while Exchange is running.')
        except Empty:
            pass

        if event_types is None:
            event_types = EventTypes.ALL

        queue = Queue()
        self.queues[event_types].append(queue)
        return queue