docs: def _build_http(http=None):
      """Construct an http client suitable for googleapiclient usage w/ user agent.
      """
      if not http:
          http = httplib2.Http(
              timeout=HTTP_REQUEST_TIMEOUT, ca_certs=HTTPLIB_CA_BUNDLE)
  
      user_agent = 'Python-httplib2/{} (gzip), {}/{}'.format(
          httplib2.__version__,
          'custodian-gcp',
          '0.1')
      return set_user_agent(http, user_agent)