message: Apply string compat function to address when creating a coordinator.
diff: @@ -481,7 +481,8 @@ class TPUClusterResolver(ClusterResolver):
  return self._environment
  def _start_local_server(self):
  - address = self._requestComputeMetadata('instance/network-interfaces/0/ip')
  + address = compat.as_text(self._requestComputeMetadata(
  + 'instance/network-interfaces/0/ip'))
  self._server = server_lib.Server(
  {
  'local': ['0.0.0.0:0']
  