headless authentification of an app to google api

I have a python app which needs (among many other things) to read a googlesheet.The line

flow = InstalledAppFlow.from_client_secrets_file(cred_file, SCOPES)

requires me to visit https://accounts.google.com/o/oauth2/auth?response_type=code&client_id=...I go there, give a manual authorization and my app works well.

Now, here is the twist.

I need to run the app on a headless machine. I only have a ssh access. It still requires me to visit https://accounts.google.com/o/oauth2/a, but I don't know how to get to that URL with my "only ssh" machine.

I could go there with a text base browser[1], but I'd like a more "programmatic" way.

[1] w3m and elinks do not work because of a lack of javascript. I did not got further in that direction.

EDIT : when I said "read googlesheet", I was oversimplifying my needs. In fact I have (among others) to list elements in a shared drive.