flask make website default to port 8080 code example
Example: how to run flask in port 80
sudo apt install authbind
sudo touch /etc/authbind/byport/80
sudo chmod 777 /etc/authbind/byport/80
authbind --deep python3 app.py
sudo apt install authbind
sudo touch /etc/authbind/byport/80
sudo chmod 777 /etc/authbind/byport/80
authbind --deep python3 app.py