Comment 2 for bug 1806399

From the attached DpkgHistoryLog.txt I can infer that the problem started after removing python3.

I'd try something like what was posted there: https://askubuntu.com/questions/914556/python-3-not-working

cd /tmp
apt-get download python3 python3.6 python3-minimal python3.6-minimal libpython3.6-minimal
sudo dpkg -i *python3*.deb
sudo apt install -f