Open app.py in the editor (recognized as python program)
To run:
From menu: Run > Run without debugging
right button then select "Run Python file in Terminal"
or open another terminal and type (.venv) victor@victorpc:contact-app$ /home/victor/Work/Learn/Python/HypermediaSystemsBook/dev/contact-app/.venv/bin/python /home/victor/Work/Learn/Python/HypermediaSystemsBook/dev/contact-app/app.py
or simply python app.py
View in browser
Point browser at http://127.0.0.1:5000, it redirects to http://127.0.0.1:5000/contacts and the contacts are listed on the page