Yes, they are great for developing modular python scripts, like for CLIs, where you might want to prototype some feature without importing the entire app.

For example, I'm working on a cli for a client that ingests a bunch of spreadsheets and processes the data in an SQLite db. Pretty lightweight, but it takes a half hour to run. Using Jupyter notebooks to import some classes and iterate on SQL queries without needing the entire corpus of data is handy.