Django migration with python3.6 ERROR:root:code for hash sha3_224 was not found

Check if your python has been updated recently. The venv might be pointing to the old one, recreating venv fixed it for us.

Running mkvirtualenv venv or virtualenv venv (depending on how you created it in the first place) should also work while keeping the installed packages.

!Mind it is really hot fix!

This issue appears in new version of python - 3.6.3.

Downgrade to 3.6.2 helped me

Here is legacy PPA: https://launchpad.net/~fkrull/+archive/ubuntu/deadsnakes/+index?batch=75&direction=backwards&start=75

Commands for further actions of downgrading python:

sudo apt install libpython3.6-minimal=3.6.2-1+xenial1 sudo apt install python3.6-minimal=3.6.2-1+xenial1 sudo apt install python3.6-stdlib=3.6.2-1+xenial1 sudo apt install python3.6=3.6.2-1+xenial1

This solved my issue:

cd /usr/bin
sudo cp python3.6 python3

Previously I had 3.6.2, after doing apt-upgrade the system was broken.