On github, you can download a Firewall Inspection Tester. This one is tested with Ubuntu (tested with 18.04 and 20.04).
You can download it at: https://github.com/gahlberg/fit?search=1

Here the commands on openSUSE Leap 15.5:

cd /home
zypper install vim git python3-pip
pip3 install click==6.6 requests==2.10.0 selenium==2.53.6 requests-toolbelt==0.7.0
git clone https://github.com/gahlberg/fit.git
cd ./fit
chmod 700 repeatFit.py
chmod 700 repeatFitMalware.py

Instead of /home you can choose any directory.