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OOP & classes

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

3 matches
OOP & classes medium

How to Implement the State Pattern in Python

Implement the State design pattern in Python by delegating behavior to state objects, letting a media player change actions dynamically without if-else chains.

state-pattern design-patterns oop
Python
class State:
    def play(self, player): pass
    def pause(self, player): pass
    def stop(self, player): pass

class PlayingState(State):
    def play(self, player):
        return "Already playing"
    def pause(self, player):
        player.state = PausedState()
        return "Pausing playback"
    def stop(self…
12 0 Open
OOP & classes medium

How to implement a Facade class to simplify subsystem calls in Python

Use a Facade class to wrap complex subsystem interactions behind a simple start() method, hiding the details and providing a clean interface.

facade design-patterns oop
Python
class CPU:
    def freeze(self):
        print("CPU: freezing")

    def jump(self, position):
        print(f"CPU: jumping to {position}")

    def execute(self):
        print("CPU: executing")


class Memory:
    def load(self, position, data):
        print(f"Memory: loading '{data}' at {position}")


class HardDr…
15 0 Open
OOP & classes medium

Understanding Multiple Inheritance Method Resolution Order in Python

This code demonstrates how Python's MRO determines which greet method is called in a diamond inheritance scenario, and prints the full MRO for class D.

multiple inheritance mro inheritance
Python
class A:
    def greet(self):
        return "Hello from A"

class B(A):
    def greet(self):
        return "Hello from B"

class C(A):
    def greet(self):
        return "Hello from C"

class D(B, C):
    pass


if __name__ == "__main__":
    d = D()
    print(d.greet())
    print(D.__mro__)
12 0 Open

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