Given that I am not able to replicate the error on my machine and that the error is happening on a line of code where libraries are being imported from grasshopper, I would guess that you are getting that error either because your GHPython or your grasshopper version is not up-to-date. Try updating these and let me know if this fixes it.
Also, Mostapha. I have changed LB_LB such that users will get a warning to update LB_LB now instead of having the component go red as in Ding’s image. The update can be found here:
I agree with Mostapha’s and Chris’ opinions. I’ve seen this error with older GhPython releases that do not have the ‘components’ library (the one that allows to use Grasshopper components natively in Python).