DeMorgan’s law is a simple law that I learned at UPT during one of my hardware classes. While it is useful in hardware it, it is also useful when writing programs.

If you have a condition like not (A and B), you can rewrite it to !A or !B.

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if __name__ == '__main__':
    a = True
    b = True

    if not (a and b):
        print("True")
    else:
        print("False")

    if not a or not b:
        print("True")
    else:
        print("False")