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How to Implement a Singleton Class in Python

This code demonstrates a classic Singleton pattern in Python by overriding __new__ to ensure only one instance of the class is created, even when instantiated multiple times.

singleton class oop

Python

class Singleton:
    _instance = None

    def __new__(cls):
        if cls._instance is None:
            cls._instance = super().__new__(cls)
        return cls._instance

    def __init__(self):
        self.value = 0


if __name__ == "__main__":
    s1 = Singleton()
    s2 = Singleton()
    s1.value = 42
    print…

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