[Divingduck]

Short question, have anything change in using the function?

I use it from time to time with a custom column to find out in what VL a book is available.

Setup:
Custom column: Column build from other columns, behaves like tags
Code: program:virtual_libraries()

Behavior:
First book will shown correctly and all following books showing "Template Error maximum recursion depth exceeded while calling a Python object" but if I click on the column of the book it shows the listed virtual libraries correct in the template editor.
Same behavior for code:
{0:'virtual_libraries()'}