Decorators on abstract methods

I would code it as two different methods just like in standard method factory pattern description.

https://www.oodesign.com/factory-method-pattern.html

class Foo(object):
    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    @some_decorator
    def my_method(self, x):
        self.child_method()

class SubFoo(Foo):
    def child_method(self, x):
        print x