[docs] [issue31811] async and await missing from keyword list in lexical analysis doc

F. Lamar <lamar.frankie@gmail.com> added the comment: I a new contributor. This seems like a simple fix. I'd be happy to work on it. I will submit ar PR on or before 10-22-17 ---------- nosy: +F. Lamar _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue31811> _______________________________________