Sorry, I misread the title "Beautiful mini language for outputing HTML in Python" as a DSL to be embedded in Python code rather than a separate text file (which is actually language agnostic after the preprocessor is done).
No worries. I am actually curious to your thoughts about DSLs. I love Python, but it is not really optimized for DSLs. You can obviously implement a DSL in Python, but embedding it is another story.