How can one stop a class from being directly instantiated in Python?

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In Python, one can prevent a class from being directly instantiated by defining the __init__() method as a private method with a double underscore (__) prefix:

class MyClass:
    def __init__(self):
        raise NotImplementedError("Cannot directly instantiate this class")

This will raise an error if anyone attempts to directly create an instance of the class:

>>> my_instance = MyClass()
NotImplementedError: Cannot directly instantiate this class