I know he made a little "bait" comment but at least he admits the simple inability for python to seriously host DSLs. If you look at any python port of a DSL (sinatra clone, cucumber clone, whatever) it's just simply ugly. It's STILL python code.
In contrast, however, I give you Cucumber scenario files. Yes, Given/When/Then are methods but it's still a very elegant DSL.
I'll do some poking into prolog and forth-based DSLs. You've peaked my interest.
If you look at Steak (https://github.com/cavalle/steak), however, this is a real native Ruby DSL, and such a thing is impossible to ever do as elegant in Python.