OAuth2 Google Calendar API Authorize Route

auth.py

# create our Flask web app
app = Flask(__name__)

# this allows transport over HTTP for development purposes, if excluded
# HTTPS is needed
os.environ['OAUTHLIB_INSECURE_TRANSPORT'] = '1'

@app.route("/authorize-user")
def auth_user():
    """
    Redirects a user to Google's authorization server to show the OAuth
    Consent screen and get user consent.
    """
    return redirect(authorization_url)