is there any way to

getValue()

or

setValue()

a Document-type field? I've tried logging an occupied field with debug and emergency to see what the value format is like (file cabinet internal ID or url or whatnot), but I keep getting

undefined

in every attempt. The end-goal is to be able to assign a Suitescript-uploaded PDF file onto the field, so the end-user can click and preview it in another tab.