You will notice that the FLASK_EXT environment variable is in your application and available to all your scripts. Any .env files you have in your project directory will also be loaded.
Once the installer has completed, you can open Python 3.6 and search for the flask command. This is how you can tell that you are running the correct version of Flask. If you don't find the flask command, you can open an administrator command prompt, type python -m pip install flask 827ec27edc