OSError: SavedModel file does not exist at: all

[iris-qq]

After it's turned into a pb file,The following error occurred using the command saved_model_cli show --dir allto view the network structure

Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.6/bin/saved_model_cli", line 11, in <module>
    sys.exit(main())
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/tensorflow/python/tools/saved_model_cli.py", line 823, in main
    args.func(args)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/tensorflow/python/tools/saved_model_cli.py", line 617, in show
    _show_tag_sets(args.dir)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/tensorflow/python/tools/saved_model_cli.py", line 59, in _show_tag_sets
    tag_sets = reader.get_saved_model_tag_sets(saved_model_dir)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/tensorflow/contrib/saved_model/python/saved_model/reader.py", line 88, in get_saved_model_tag_sets
    saved_model = read_saved_model(saved_model_dir)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/tensorflow/contrib/saved_model/python/saved_model/reader.py", line 55, in read_saved_model
    raise IOError("SavedModel file does not exist at: %s" % saved_model_dir)
OSError: SavedModel file does not exist at: all