Thanks for that suggestion. As usual when suggesting new functionalities, you should first experiment by creating a custom function class in one of your projects. This may reveal any blocker functionality that would need some change in Django itself. Then you may start to prepare a proof-of-concept patch showing how it would look inside Django’s code. Of course, at some point you should also get an approved ticket in the ticket tracker, but if we get more approvals of this idea in this thread, that would help.
+1 from me at least (unless we discover hard blockers in the implementation).