class MyClass(object):
    _instance = None
 
    @classmethod
    def get_instance(cls, *args, **kwargs):
        if cls._instance is None:
            cls._instance = super().__new__(cls, *args, **kwargs)
            cls.__init__(cls._instance, *args, **kwargs)
        return cls._instance
 
    def __init__(self):
        #so something
        self.fun()
        #so something
 
    def fun(self):
        print("Hello, World!")
 
print(MyClass.get_instance())
 

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