Get Parents from Linked Document

Hi guys
I can no longer recover the parents of parts from a linked model
For information, the knots were already working before
thank you in advance
an idea?

below the error given by pyton “clokwork”


You can show result before that, try with demo .

thank you for your reply
you are a linked model?
for information, the parts are not in the linked model
So I have an empty list

Yes, i have
You can share file rvt include with link?