Vim code folding: ON at top level, OFF at 2nd & 3rd levels, ON at 4th level - how do I accomplish this?

Vim code folding: ON at top level, OFF at 2nd & 3rd levels, ON at 4th
level - how do I accomplish this?

I have the following settings in my .vimrc file:
set foldnestmax=2
set foldmethod=indent
set foldcolumn=4
I'm working primarily with python and want folding based on indentation.
However, when I open a top-level fold, I would like the code beneath it
NOT to be folded for the next 2 - 3 levels, so that I can better summarize
what is going on. However, the very deep stuff - 4 or more indentations
in, I would like to have folded.
How can I accomplish this?