[docs] [issue14050] Tutorial, list.sort() and items comparability

Change by Raymond Hettinger <raymond.hettinger@gmail.com>: ---------- pull_requests: +15091 pull_request: https://github.com/python/cpython/pull/15381 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue14050> _______________________________________