[docs] [issue17894] Edits to descriptor howto

Ezio Melotti added the comment: Attached a patch that rephrases part of the suggestions made by Ned. ---------- nosy: +ezio.melotti Added file: http://bugs.python.org/file30125/issue17894.diff _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue17894> _______________________________________