Does this mean the import mechanism caches loaded module, but not where to find non imported things ? I would expect that it crawl dirs from the PYTHON PATH once and then get data from a cache. I know you can extend the PYTHON PATH dynamically, but you could intercept that in dunder methods to update said cache.

Also: for the same interpreter, the same "*.pyc" files and the same PYTHON PATH, we could dump a cache file and share it across interpreter starts if no dirs in PYTHON PATH have been touched.

If it's not done, then it might be interesting to bring that up to the Python ideas mailing list.