[docs] [issue28749] Fixed the documentation of the mapping codec APIs

Serhiy Storchaka added the comment: Updated patch addresses Xiang's and Victor's comments. ---------- Added file: http://bugs.python.org/file45623/docs-PyUnicode_Translate-2.patch _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue28749> _______________________________________