Python: How to replace a property with a regular attribute?

You could assign to the class, instead of the instance:

MyClass.management_form = property(self.myfunc)

Of course, this changes the class itself for all instances (even preexisting ones). If this is OK, you can also call it exactly once, rather than in every derived-class constructor (which I'm guessing is what you're doing now).

Otherwise, you can override it in the derived class in the usual manner:

class MyOtherClass(MyClass):
    def _new_mf(self):
        # Better code
        return form
    management_form = property(new_mf)