result = service.users().stop(userId='me').execute()
you forgot execute method, until and unless you call execute method, your statements do nothing.
Here's a small guide how to work with google apis. go to https://developers.google.com/gmail/api/quickstart/python and observe the code, service.users().labels().list(userId='me').execute() then go to Google API Explorer and select your service let's say Gmail API you want to use https://developers.google.com/apis-explorer/#p/gmail/v1/ , there you will see services and description,like this
gmail.users.labels.list
here gmail is service object in your python code, and remaining were the methods, execute corresponds to execute button here in this page https://developers.google.com/apis-explorer/#p/gmail/v1/gmail.users.labels.list