procfile heroku for flask code example

Example 1: procfile flask

Example of what the procfile might look like for a flask app:
web: gunicorn app.py app:app

Or maybe this is for the development app:
web: python app.py

Example 2: heroku python heroku port issue

import os 
port = int(os.environ.get('PORT', 33507))  # add these lines in code
app.run(host=args.host, port=port, debug=True)  

heroku config:add PORT=33507   # run this command once you upadte the code in terminal