flask run as port 80 code example

Example 1: flask give port number

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=80)

Example 2: 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