Decorators on bound methods with access to class and his ancestors

When I decorated the bound method in Python class, I need get some info in this decorator from outer class. Is that possible?

For example:

def modifier(func):
    import sys
    cls_namespace = sys._getframe(1).f_locals
    cls_namespace['data']  # dictonary has no key 'data'
    ...
    return func

class Parent:
    data = "Hi!"

class Child(Parent):

    @modifier
    def method(self):
        pass

the cls_namespace is just incomplete namespace of current class without data field that I need to get.

Is there ways to get it in decorator?