Python script to access my Google Drive

I wrote a python script to access my Google Drive: list folders, upload and download files, etc. I believe that a few years ago this script worked already, but when I tried to execute it today, the “Unverified app screen” appeared. After some search in the topic, I read about “my users”, “publishing” my app and “application homepage link”. What?? Hang on a second! I simply want to access my Google Drive files from a python script without external users and without publishing it. I want to use my app alone. I think this should be a straightforward thing but it looks overcomplicated to me…

To tell the truth, I am sick and tired of reading lots and lots of information on Google, so I decided to post a question here.

What am I doing wrong? What information do I miss? Can I set somewhere that my app is private?