[docs] [issue11762] Ast doc: warning and version number

Georg Brandl <georg@python.org> added the comment: Sounds good to me, except for "Use *ast.__version__* to work across versions." which is not quite clear. While talking about version numbers, we should probably also document *what changed* between those versions. ---------- nosy: +georg.brandl _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue11762> _______________________________________