code: def by_user_name_and_security_code(cls, user_name, security_code, db_session=None):
          
          db_session = get_db_session(db_session)
          query = db_session.query(cls.model)
          query = query.filter(
              sa.func.lower(cls.model.user_name) == (user_name or "").lower()
          )
          query = query.filter(cls.model.security_code == security_code)
          return query.first()
docs: fetch user objects by user name and security code
  
          :param user_name:
          :param security_code:
          :param db_session:
          :return: