code: def DetectGce():
      
      metadata_url = 'http://{}'.format(
          os.environ.get('GCE_METADATA_ROOT', 'metadata.google.internal'))
      try:
          o = urllib_request.build_opener(urllib_request.ProxyHandler({})).open(
              urllib_request.Request(
                  metadata_url, headers={'Metadata-Flavor': 'Google'}))
      except urllib_error.URLError:
          return False
      return (o.getcode() == http_client.OK and
              o.headers.get('metadata-flavor') == 'Google')
docs: Determine whether or not we're running on GCE.
  
      This is based on:
        https://cloud.google.com/compute/docs/metadata#runninggce
  
      Returns:
        True iff we're running on a GCE instance.