Patch #1075928: AUTH PLAIN in smtplib.
Patch #1075928: AUTH PLAIN in smtplib.

smtplib can not log in to some server using command AUTH PLAIN, it sends
``user\0user\0pass'' to the server, but ``\0user\0pass'' has better
compatibility.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator