Some entities can be deleted with some conditions. These conditions are checked by the method can_delete in their Data model. But it just returns a boolean and their view component contains some logic to figure out why it can not be deleted. In the MVC pattern, this logic should be in the back-end only, and the View should just have to make a switch case. A possibility might be to make can_delete return more than a boolean, or to have an additional wrapping method.