Import Error

[ZrW00]

When I import openbackdoor after running python setup.py install, ImportError occurs:
ImportError: packaging>=20.0 is required for a normal functioning of this module, but found packaging==19.2.
Try: pip install transformers -U or pip install -e '.[dev]' if you're working with git main

Actually, the packaging version in my environment is 23.1, I don't know how this error occur. After uninstalling and reinstalling openbackdoor for several times, it still remains the same.