Saving bunch of files throught GH Python

Im working right now on script witch should to save some different sizes of item into STP, or STL file sequence. However im new to GH python. And know a very little about type parameters.
I can find my empty Brep node (marked with red on image), and Baked from GH objects in the Active Rhino doc. Just can`t find a way to append found object to mine Brep node which empty and is in GH doc.
As I found out through mine searches in google, there is way to do it all only is script (I mean select and save objects to particular path with certain name(based on sizes)) without finding Nodes in my GH doc.

p.s. If any possibilities to find how to access Elefront parameters directly prom python. No chance to find any definitions on google. May be mine request are not best ones. but found none results on “Elefront and python” in any combinations I tried.