It is using a few missing features in _dis module.
Maybe adding them will not be enough for modulefinder due to bytecode imcompatibility.But adding dis items will be a good issue to start looking at RustPython project.
To add a new python module, check this article: https://rustpython.github.io/blog/2020/04/04/how-to-contribute-by-cpython-unittest.html
See #3863 for errors