The __invert__ Method

What is the purpose of the __invert__ method? I was exploring Python internals and came across: >>> dir(__builtins__.int) ['__abs__', '__add__', '__and__', '__bool__', '__

Solution 1:

__invert__ is the implementation of the "binary not" operator ~ -- it has absolutely nothing to do with any formal definition of the word "invert" in mathematics

for the integer 0, using 2s complement, the binary negation of 0b000...000 is 0b111...111 -- or -1 in decimal

>>> ~int()
-1
>>> int().__invert__()
-1
>>> ~0
-1