title: Gsuite Classroom Api failing to add students and teachers
body: <p>I am implementing google's classroom api withing my domain. As suggested by the <a href="https://developers.google.com/classroom/guides/manage-courses" rel="nofollow noreferrer">documentation</a> I am creating a course. I have created a service account and assigned the necessary scopes for that account and I use an admin account as a delegated account. The document states that admins can directly create courses and I my course creation system is working. It also says that admins can directly add teachers and students. When I try to add students or teachers to a course it throws an error <code>Request had insufficient authentication scopes</code> but I have the correct classroom scope from this <a href="https://developers.google.com/identity/protocols/oauth2/scopes" rel="nofollow noreferrer">link</a>.
  Am I missing something? Any suggestion would be kindly appreciated.</p>
  
  <pre class="lang-py prettyprint-override"><code>service_credentials = ServiceAccountCredentials.from_p12_keyfile('aServiceAccount.iam.gserviceaccount.com', 
  '*.p12', 'notasecret',
  scopes=['https://www.googleapis.com/auth/admin.directory.user',
  'https://www.googleapis.com/auth/classroom.courses', 
  'https://www.googleapis.com/auth/calendar'])
  credentials = service_credentials.create_delegated(
              'anAdmin@domain')
  class_service = build('classroom', 'v1',
                                credentials=credentials)
  directory_service = build('admin', 'directory_v1',
                                    credentials=credentials)
  calendar_service = build('calendar', 'v3',
                                   credentials=credentials)
  course = {
              'name': 'This is dummy course',
              'section': 'dummy section',
              'descriptionHeading': 'Dummy course',
              'courseState': 'ACTIVE',
              'ownerId': 'anAdmin@domain' # also in the teachers group
          }
  response = class_service.courses().create(body=course).execute()
  course_id = response.get('id')
  course_code = response.get('enrollmentCode')
  teacher = {'userId': 'anotherUserFromTeachersGroup@domain'}
  class_service.courses().teachers().create(courseId=course_id,body=teacher).execute()
          # error : Request had insufficient authentication scopes
  student = {'userId': 'user@domain'}
  class_service.courses().students().create(
              courseId=course_id, enrollmentCode=course_code, body=student).execute()
          # error : Request had insufficient authentication scopes
  </code></pre>