The observer pattern implementation demo with Python

observer-pattern-demo.py

class Observable: 
    def __init__(self, *args, **kwargs):
        self.__observers = []
    
    def register_observer(self, observer):
        self.__observers.append(observer)
    
    def notify_observers(self, *args, **kwargs):
        for observer in self.__observers:
            observer.notify(self, *args, **kwargs)

class Observer:
    def __init__(self, observable):
        observable.register_observer(self)

    def notify(self, observable, *args, **kwargs):
        print('Got', args, kwargs, 'From', observable)

subject = Observable()
observer = Observer(subject)
subject.notify_observers('SIGNAL')

Wikipedia reference: https://en.wikipedia.org/wiki/Observer_pattern