Custom add condition for json in admin panel?

Question

Django

Json arrives, in the admin panel you need the ability to somehow filter it by a condition that you can add yourself.
Let's say if
{"Key1" : "Value1", "Key2" : "Value2"} arrived
In the admin panel, you need a field so that you can write if .get('Key1') > .get('Key2') then some function
Or how to do it better, please tell me, because otherwise in the first case, as I understand it, I will have to write an engine to process the condition from the admin panel.