def concept_names(self):
        """
        [str] 概念股分类，例如：’铁路基建’，’基金重仓’等（股票专用）
        """
        try:
            return self.__dict__["concept_names"]
        except (KeyError, ValueError):
            raise AttributeError(
                "Instrument(order_book_id={}) has no attribute 'concept_names' ".format(self.order_book_id)
            )