该接口用于撤销指定的未成交或部分成交订单。通过传入证券账号 account_no 及订单编号 order_id,向交易所发起撤单请求,将订单状态变更为已撤单或部分撤单。撤单操作仅支持处于可撤单状态的订单,撤单成功后订单将不再参与撮合。This interface is used to cancel a specified unfilled or partially filled order. By providing the account number account_no and order ID order_id, it submits a cancellation request to the exchange and changes the order status to cancelled. Cancellation is only supported for orders in a CanceledStatus or PartialWithdrawal. Once successfully cancelled, the order will no longer participate in matching.