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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 cancel(self, event):
 """Remove an event from the queue. This must be presented the ID as returned by enter(). If the event is not in the queue, this raises ValueError. """

        with self._lock:
            self._queue.remove(event)
            heapq.heapify(self._queue)