def _maybe_create_download_node(self):
if not self._download_status:
ds = DownloadStatus(self._verifycap.storage_index,
self._verifycap.size)
if self._history:
self._history.add_download(ds)
self._download_status = ds
if self._node is None:
self._node = DownloadNode(self._verifycap, self._storage_broker,
self._secret_holder, self._terminator,
self._history, self._download_status)
