[docs] [issue20699] Document that binary IO classes work with bytes-likes objects

Serhiy Storchaka added the comment: The patch LGTM. But native speaker should check documentation part. ---------- title: Behavior of ZipFile with file-like object and BufferedWriter. -> Document that binary IO classes work with bytes-likes objects _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue20699> _______________________________________