Python's module importing / $PYTHONPATH lookup/traversal is incredibly inefficient, especially with cold FS caches... I've worked at places where we've signifi

Python's module importing / $PYTHONPATH lookup/traversal is incredibly inefficient, especially with cold FS caches... I've worked at places where we've significantly patched the logic (in a way which breaks compatibility in some cases, so couldn't be up-streamed) which makes Python startup / module loading with hundreds of paths in $PYTHONPATH orders of magnitude faster...