Can't run webServer.py

1654327207

Hi.I'm trying to run raspClaws Spider Robot Kit for RPi but I'm stucking.
When I run webServer.py , I get such the error below;

AttributeError: 'NoneType' object has no attribute 'all'

and I can't continue.

What can I do to fix this problem?

<My environment>
・Using raspberry pi 2b
・OS image is from official documentation (https://www.adeept.com/learn/detail-37.html)

If you need more information, please ask me.
Sorry for poor English.