service_account_sample.py

import os
import httplib2
from apiclient.discovery import build
from oauth2client.client import SignedJwtAssertionCredentials

http = httplib2.Http()

SCOPES = [
  'https://www.googleapis.com/auth/calendar'
]
SERVICE_ACCOUNT_EMAIL = '801883730557-744ngc0s9eh5md75gehkb98acppjjr61@developer.gserviceaccount.com'
KEY_PATH = os.path.expanduser('~/privatekey.p12')
DOMAIN_USER = 'richie@richieforeman.net'  # somebody on the domain


def main():
  credentials = SignedJwtAssertionCredentials(
      service_account_name=SERVICE_ACCOUNT_EMAIL,
      private_key=file(KEY_PATH).read(),
      scope=SCOPES,
      sub=DOMAIN_USER)
  
  credentials.authorize(http)
  service = build('calendar', 'v3', http=http)
  # fetch simple calendar list.
  print service.calendarList().list().execute()

if __name__ == '__main__':
  main()