New submission from Dawid Gosławski :
Shutil's which implementation does not work correctly when someone set's empty
item in `PATHEXT` environment variable. Example:
set PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC;.RB;.RBW;
I'm not 100% sure how I got this in my PATHEXT
Dawid Gosławski added the comment:
Will that be backported also to Python2.7 ? I personally do not see a reason to
teach old dog new tricks but it seems appropriate in such core things. New
users could transition easier, otherwise this would be next py2<->py3
difference to explain ever
