code: def create_attribute_model(self, initial_value=None):
          # type: (Any) -> AttributeModel
          
          attr = self.attribute_class(meta=self, value=initial_value)
          return attr
docs: Make an AttributeModel instance of the correct type for this Meta
  
          Args:
              initial_value: The initial value the Attribute should take
  
          Returns:
              AttributeModel: The created attribute model instance