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OOP & classes

Classes, instances, methods, dataclasses, and object-oriented design in Python.

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OOP & classes medium

Observer Pattern in Python: Notify Listeners

Implement the Observer design pattern in Python with a Subject class that manages listeners and notifies them with messages.

design-pattern observer oop
Python 
class Subject:
    def __init__(self):
        self._observers = []

    def attach(self, observer):
        self._observers.append(observer)

    def detach(self, observer):
        self._observers.remove(observer)

    def notify(self, message):
        for observer in self._observers:
            observer.update(me…
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