In fact using BBEdit as editor folding is just around the corner... the simple tuning is to change ".txt" file name extension in ".py" in this AppleScript handler:
Explanation:
The conventions to encode in a compact way the hierarchy of the GUI elements are identical to that of the Python code: it is therefore enough to take full advantage of this homology by transforming the temporary text file into a pseudo Python file, by changing the extension, so that BBEdit automatically activates the folding 
Before:
After
For example, "scroll bar 1" elements are folded:
-Alain