Can I modify existing diagrams?

[sammerlahn]

I would like to modify previously created diagrams iteratively via python code. Is it possible with DrawPy?
I.e. I need to

• open an existing file
• find the page I created before (or just the first one)
• find previously created objects (by id or by some internal data on the object)
• add new objects if not existing
• add new objects to new or existing parent containers

How would I be able to that?