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OOP & classes

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

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OOP & classes medium

How to Implement the Command Pattern with Undo in Python

Python code demonstrating the Command design pattern with undo and redo support using action objects and a history manager.

command-pattern design-patterns oop
Python 
class Command:
    def execute(self):
        raise NotImplementedError

    def undo(self):
        raise NotImplementedError


class AddTextCommand(Command):
    def __init__(self, document, text):
        self.document = document
        self.text = text

    def execute(self):
        self.document.append(self.tex…
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