[R5RS][1] is simple.

To get any work done with it, though, you need to write your own Python.

[1]: https://conservatory.scheme.org/schemers/Documents/Standards...

That is admittedly a bit of an abomination (very powerful though) but the language itself is very simple. It just allows the creation of DSLs which is what format really is.

I believe GP is using it in the literal etymologically correct way in the vein of Rich Hickey: https://youtu.be/LKtk3HCgTa8?feature=shared

Pedantically, Common Lisp being a Lisp-2 vs a Lisp-1 arguably makes it a duplex vs a simplex…