thx for your reply
before the discussion, i'm not well eng. but i understand your answer.
relativePathTo, it just extracting string path of node by node... my question means the way searching nodes function.
i research the way about python working process in block box and testing for simply.
in more then deep blackbox level, pwd or node('.') or node('./[node]') are access working. can access node, parms, set value, anythings
but, searching node function(children, parent, etc...) was blocked by permission error. even using accessed node.
as i think, pwd or node('./[node]') can accessing node by relative path, but children or parent function has accessing by only absolute path.
because blockbox is blocked of outside accessed. but, inside the blockbox was accessed worked. (like a shell)
wonder how i accessing children nodes function using by relative path in blockbox?