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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 _has_expired(self):
 """ Has this HIT expired yet? """

        expired = False
        if hasattr(self, 'Expiration'):
            now = datetime.datetime.utcnow()
            expiration = datetime.datetime.strptime(self.Expiration, '%Y-%m-%dT%H:%M:%SZ')
            expired = (now >= expiration)
        else:
            raise ValueError("ERROR: Request for expired property, but no Expiration in HIT!")
        return expired