This is a template project bootstraps a Flask webapp and has user authorization flow with Google accounts.
Steps on getting your app to work.
Setup your development environment (pyenv or virtualenv recommended) and install the requirements.
pip install -r requirements.txt
Configure your app in config_template.py and save as config.py
Go to Google's dev console and on the top left nav bar click the drop down and Create Project. Go through the flow to create you project, and select it from the drop down.
Click API & Auth > Credentials on the left sidebar menu, click the OAuth consent screen and fill out the info.
Click Credentials Tab and add + select OAuth 2.0 Client ID credentials. Select Web application as the type, name the app anything you want. Set the javascript origins to http://localhost:5000 and the Authorized redirect URIs to http://localhost:5000/gCallback for now. You can create a new set of credentials when you are ready to run on different environments.
After you complete those steps and click create, you will have the option to download the json file of the client secrets. Save this file in your root directory as client_secrets.json
python -m run
Are you as clueless about oauth2 workflow as I was? Digital Ocean has a great knowledge dump of it. Check it out here