@api_utils._eager_tasklet
  @ndb.tasklet
  def do_request_async(self, url, method='GET', headers=None, payload=None,
                       deadline=None, callback=None):
    if headers is None:
      headers = {}
    if 'x-goog-api-version' not in headers:
      headers['x-goog-api-version'] = '2'
    headers['accept-encoding'] = 'gzip, *'
    try:
      resp_tuple = yield super(_StorageApi, self).do_request_async(
          url, method=method, headers=headers, payload=payload,
          deadline=deadline, callback=callback)
    except urlfetch.DownloadError, e:
      raise errors.TimeoutError(
          'Request to Google Cloud Storage timed out.', e)

    raise ndb.Return(resp_tuple)
Inherit docs.
dataset/ETHPy150Open GoogleCloudPlatform/billing-export-python/cloudstorage/storage_api.py/_StorageApi.do_request_async