Bug#950147: sagemath ftbfs with python 3.8

[Matthias Klose]

Package: src:sagemath
Version: 9.0-1
Severity: important
Tags: sid bullseye
User: debian-python at lists.debian.org
Usertags: python3.8

sagemath ftbfs with python 3.8.  Not sure if you already can check that in
Debian, however in Ubuntu, there seem to be a lot of failing tests, plus the
tests failing because of too many open files (googling about that, I found some
hints, but just for MacOSX).

Build logs at
https://launchpad.net/ubuntu/+source/sagemath/9.0-1build1

Any help would be appreciated.