code: def values_list(self, *fields, **kwargs):
          
          flat = kwargs.pop('flat', False)
          if kwargs:
              raise TypeError('Unexpected keyword arguments to values_list: %s'
                              % (kwargs.keys(),))
          if flat and len(fields) > 1:
              raise TypeError("'flat' is not valid when values_list is called with more than one field.")
          clone = self.only(fields)
          clone._values_list = True
          clone._flat_values_list = flat
          return clone
docs: Instructs the query set to return tuples, not model instance