How to use the starthinker.util.auth.get_service function in starthinker

def test_string_credentials_user(self):
    with open(self.user_file, 'r') as json_file:
      project.initialize(_user=json_file.read())

    service = get_service('oauth2', 'v2', 'user')
    response = service.userinfo().get().execute()

    self.assertIn('email', response)
    self.helper_refresh()

def test_string_credentials_service(self):
    with open(self.service_file, 'r') as json_file:
      project.initialize(_service=json_file.read())

    service = get_service('cloudresourcemanager', 'v1', 'service')
    response = service.projects().list().execute()

    self.assertIn('projects', response)

def object_delete(auth, path):
  bucket, filename = path.split(':', 1)
  service = get_service('storage', 'v1', auth)
  return service.objects().delete(bucket=bucket, object=filename).execute()

def object_put(auth, path, data, mimetype='application/octet-stream'):
  bucket, filename = path.split(':', 1)
  service = get_service('storage', 'v1', auth)

  media = MediaIoBaseUpload(data, mimetype=mimetype, chunksize=CHUNKSIZE, resumable=True)
  request = service.objects().insert(bucket=bucket, name=filename, media_body=media)

  response = None
  errors = 0
  while response is None:
    error = None
    try:
      status, response = request.next_chunk()
      if project.verbose and status: print "Uploaded %d%%." % int(status.progress() * 100)
    except HttpError, e:
      if e.resp.status < 500: raise
      error = e
    except (httplib2.HttpLib2Error, IOError), e:
      error = e

def object_get_chunks(auth, path, chunksize=CHUNKSIZE, encoding=None):
  bucket, filename = path.split(':', 1)
  service = get_service('storage', 'v1', auth)

  data = BytesIO()
  request = service.objects().get_media(bucket=bucket, object=filename)
  media = MediaIoBaseDownload(data, request, chunksize=chunksize)

  retries = 0
  done = False
  while not done:
    error = None
    try:
      progress, done = media.next_chunk()
      if progress: print('Download %d%%' % int(progress.progress() * 100))
      data.seek(0)
      #yield data
      yield data.read().decode(encoding) if encoding else data
      data.seek(0)

def sheets_batch_update(auth, sheet_url_or_name, data):
  service = get_service('sheets', 'v4', auth)
  sheet_id = sheets_id(auth, sheet_url_or_name)
  API_Retry(service.spreadsheets().batchUpdate(spreadsheetId=sheet_id, body=data))

def sheets_get(auth, sheet_url_or_name):
  sheet_id = sheets_id(auth, sheet_url_or_name)
  if sheet_id: 
    service = get_service('sheets', 'v4', auth)
    return API_Retry(service.spreadsheets().get(spreadsheetId=sheet_id))
  else: 
    return None

def bucket_access(auth, project, name,  role, emails=[], groups=[], services=[], domains=[]):
  service = get_service('storage', 'v1', auth)

  entities = map(lambda e: 'user-%s' % e, emails) + \
    map(lambda e: 'group-%s' % e, groups) + \
    map(lambda e: 'user-%s' % e, services) + \
    map(lambda e: 'domain-%s' % e, domains)

  for entity in entities:
    body = {
      "kind": "storage#bucketAccessControl",
      "bucket":name,
      "entity":entity,
      "role":role
    }
    API_Retry(service.bucketAccessControls().insert(bucket=name, body=body))

def sheets_clear(auth, sheet_url, sheet_tab, sheet_range):
  if project.verbose: print 'SHEETS CLEAR', sheet_url, sheet_tab, sheet_range
  service = get_service('sheets', 'v4', auth)
  sheet_id = sheets_id(sheet_url)
  API_Retry(service.spreadsheets().values().clear(spreadsheetId=sheet_id, range=sheets_tab_range(sheet_tab, sheet_range), body={}))

def bucket_get(auth, name):
  service = get_service('storage', 'v1', auth)
  try: return service.buckets().get(bucket=name).execute()
  except HttpError, e:
    if e.resp.status == 404: return None
    elif e.resp.status in [403, 500, 503]: sleep(5)
    else: raise