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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 enterabs(self, time, priority, action, argument=(), kwargs=_sentinel):
 """Enter a new event in the queue at an absolute time. Returns an ID for the event which can be used to remove it, if necessary. """

        if kwargs is _sentinel:
            kwargs = {}
        event = Event(time, priority, action, argument, kwargs)
        with self._lock:
            heapq.heappush(self._queue, event)
        return event