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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 _expire_data(self):
 """ Remove all expired entries. """

        expire_time_stamp = time.time() - self.expire_time
        self.timed_data   = {d: t for d, t in self.timed_data.items()
                             if t > expire_time_stamp}