Python Decorators using self

I spent some time to figure out so i decide to share in case anyone is interested.
If you want to access self (instanse where decorator is called from) you can use args[0] inside the decorator.

Example:

states = {"a":"b", "b":"c", "c":"d", "d","end"}
class Foo:
     #skip some staff
    def will_change_state(f):
            def wrapper(*args):
                ret =  f(*args)
                args[0].change_state()
                return ret
            return wrapper

     def change_state(self):
            self.state = states[self.state]

     @will_change_state
     def func1(self):
           pass

     @will_change_state
     def func2(self):
           pass