How to use the Google library to work with its services?

Question

Flask

I need to get acquainted with the Google API, I took their google-api-python-client library, created an API key and want to try to pull something from Google Play, but I didn’t figure out how to use the library. Are there any articles or tutorials?
Further 3 lines of code, it is not clear what to do.

import apiclient
API_KEY = 'API_KEY'
service = apiclient.discovery.build('androidpublisher','v2',developerKey=API_KEY)

Help me figure out what's going on in this life.