I got:

! Text line contains an invalid character.
l.66796 ...de{subprocess.Popen()}}}} の stream ^^P
                                                  引数など、ファイル記述子つ...

while building with xelatex, and found where it come from, it's from library/socket.po:

#: ../../library/socket.rst:1072
msgid ""
"On Windows, the file-like object created by :meth:`makefile` cannot be used "
"where a file object with a file descriptor is expected, such as the stream "
"arguments of :meth:`subprocess.Popen`."
msgstr ""
"Windows では、 :meth:`subprocess.Popen` の stream ^P引数など、ファイル記述子つき file "
"オブジェクトが期待されている場所では、 :meth:`makefile` によって作成される file-like オブジェクトは使用できません。"

Problem is the ^P right after the word stream. This ^P is the representation emacs makes of the charachter, which is a 0x10, so a data link escape.

git grep $'\x10' 
library/socket.po:"Windows では、 :meth:`subprocess.Popen` の stream ^P引数など、ファイル記述子つき file "