shading principled_bsdf

hello,
thank you very much for this script! it's really interesting. Little by little, I'm learning to use it and it's really super powerful! 
I have a question about shading... I thought I saw that we have access to nodes like "principled_bsdf" etc. Does this mean we can use geometry_script to create materials? and if so there would be an example? 
THANKS