We have support for duckdb (and CSVs and Parquet through duckdb). We don't support python, but some people have also told us they have used evidence as the front-end for a python project - used python to do data transformation and calculations, then dumped the results into a duckdb file in an evidence project and built the visuals and narrative in evidence.
"Containerized" approaches with evidence are also quite interesting - lets you combine several tools and use evidence as the last mile. Here's a great example: https://github.com/matsonj/nba-monte-carlo
Something like this but with duckdb + python support would be nice.
In fact, I would imagine this kind of things to be a good use case for introducing templating in jupyter notebooks.