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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 _zone_expired(self, zone):
 """ Determine if a zone is expired or not. :param zone: zone number :type zone: int :returns: whether or not the zone is expired """

        return (time.time() > self._zones[zone].timestamp + Zonetracker.EXPIRE) and self._zones[zone].expander is False