test_gce_integration.py

from googleapiclient.discovery import build
from oauth2client.client import GoogleCredentials
from oauth2client.contrib.gce import AppAssertionCredentials


def main():
    creds = GoogleCredentials.get_application_default()
    client = build('compute', 'v1', credentials=creds)
    print(client.instances().list(project='project-id', zone='zone').execute())

    creds = AppAssertionCredentials()
    client = build('compute', 'v1', credentials=creds)
    print(client.instances().list(project='project-id', zone='zone').execute())


if __name__ == '__main__':
    main()