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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 is_expired_token(self, client):
 """ For a given client will test whether or not the token has expired. This is for testing a client object and does not look up from client_id. You can use _get_client_from_cache() to lookup a client from client_id. """

        if 'expires' not in client:
            return True

        expires = dateutil.parser.parse(client['expires'])
        if expires < datetime.datetime.now():
            return True

        return False