[issue37330] open(): remove 'U' mode, deprecated since Python 3.3

[STINNER Victor]

STINNER Victor <vstinner at redhat.com> added the comment:

I reported the issue to docutils. In fact, docutils FileInput class was already fixed to prevent the deprecation warning, but there was no release yet:
https://sourceforge.net/p/docutils/bugs/363/

----------

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue37330>
_______________________________________