def save(self, session_id, session_data, expires=None):
        session_data = session_data if session_data else {}
        if expires:
            session_data.update(__expires__=expires)
        session_data = pickle.dumps(session_data)
        self.__create_redis_client()
        self.client.set(session_id, session_data)
        if expires:
            delta_seconds = int((datetime.utcnow() - expires).total_seconds())
            self.client.expire(session_id,delta_seconds)
dataset/ETHPy150Open MitchellChu/torndsession/torndsession/redissession.py/RedisSession.save/swapped operands of `-`