I got up through the end of chapter for of Crafting Interpreters with my Python version. It too a little finagling, and the result is kind of awkward (as a result of how I wrote the code), but it works, at least according to the tests I wrote. It's nice having tests; I never got experienced with any testing libraries in Lua like I did with pytest and coverage.py.
Anyway, I guess I don't have much more to say. It's late, and the basic lexer for Lox isn't too impressive.