code: def save_many(self, models, joinings=None):
          
          if joinings is None:
              joinings = {}
  
          for key, model in enumerate(models):
              self.save(model, joinings.get(key), False)
  
          self.touch_if_touching()
  
          return models
docs: Save a list of new models and attach them to the parent model
  
          :type models: list
          :type joinings: dict
  
          :rtype: list