code: def get_openOrders(self, acc_id=None, symbol=None, side=None, size=None, _async=False):
          
          params = {}
          path = '/v1/order/openOrders'
          if all([acc_id, symbol]):
              params['account-id'] = acc_id
              params['symbol'] = symbol
          if side:
              assert side in ['buy', 'sell']
              params['side'] = side
          if size:
              params['size'] = size
  
          return api_key_get(params, path, _async=_async)
docs: 查询未成交订单
          :param acc_id: 帐号ID
          :param symbol: 交易对ID
          :param side: 交易方向，'buy'或者'sell'
          :param size: 记录条数，最大500
          :return: