True False and None

In Python 2, True, False and None are built-in constants. Which means it’s possible to reassign them.

True, False = False, True
True   # False
False  # True

You can’t do this with None since Python 2.4.

None = None  # SyntaxError: cannot assign to None

In Python 3, True, False, and None are now keywords.

True, False = False, True  # SyntaxError: can't assign to keyword

None = None  # SyntaxError: can't assign to keyword

Found a mistake? Have a question or improvement idea? Let me know.

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