docs: def __modify(self, client_id, client_secret, **kwargs):
          """Call documentation: `/app/modify
          <https://www.wepay.com/developer/reference/app#modify>`_, plus extra
          keyword parameter:
          
          :keyword bool batch_mode: turn on/off the batch_mode, see 
             :class:`wepay.api.WePay`
  
          :keyword str batch_reference_id: `reference_id` param for batch call,
             see :class:`wepay.api.WePay`
  
          :keyword str api_version: WePay API version, see
             :class:`wepay.api.WePay`
  
          """
          params = {
              'client_id': client_id,
              'client_secret': client_secret
          }
          return self.make_call(self.__modify, params, kwargs)