code: def order(self, value):
          
          if isinstance(value, str):
              value = [value]
          self._order[:] = value
docs: Set the fields used to sort query results.
  
          Sort fields will be applied in the order specified.
  
          :type value: str or sequence of strings
          :param value: Each value is a string giving the name of the
                        property on which to sort, optionally preceded by a
                        hyphen (-) to specify descending order.
                        Omitting the hyphen implies ascending order.