The __invert__ methods, which controls the behaviour of the ~ operator, of 
Integers and ints are different.

In Python, for an int x, its invert ~x is defined to be its two's 
complement and is given by -1-x 
<https://wiki.python.org/moin/BitwiseOperators>.

On the other hand, in Sage for an Integer x 
(from sage.rings.integer.Integer), its __invert__ is defined to be 1 / x 
<https://github.com/sagemath/sage/blob/master/src/sage/rings/integer.pyx#L5999-L6011>
.

Unfortunately this difference means that ~x different results in Sage and 
Python and so is causing some of my scripts and packages that run under 
Python to break under Sage. Most notably, that under Sage ~0 raises a 
"ZeroDivisionError: Rational division by zero" error rather than returning 
-1.

Looking through the git history it appears that this has been the 
convention since at least October 2006 
<https://github.com/sagemath/sage/blob/b94db547579596d7979e28aa9aff1cdb45193bcc/src/sage/rings/integer.pyx#L1590-L1593>.
 
Is there a reason why __invert__ was chosen to act this way rather than 
match the Python convention?

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