[docs] [issue15997] NotImplemented needs to be documented

Max added the comment: I agree about reflected operation, although the wording could be clearer ("will try reflected operation" is better worded as "will return the result of the reflected operation called on the swapped arguments".) But what does it mean "or some other fallback"? And what if the reflected operation or the fallback again return NotImplemented or is actually not implemented. Is it somewhere else in the docs? ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue15997> _______________________________________