docs: def _close_writable(self):
          """
          Close the object in write mode.
          """
          # Wait segments upload completion
          for segment in self._write_futures:
              segment['etag'] = segment['etag'].result()
  
          # Upload manifest file
          with _handle_client_exception():
              self._client.put_object(self._container, self._object_name, _dumps(
                  self._write_futures), query_string='multipart-manifest=put')