In short, the module isn't being added to the package's namespace because we are directly modifying sys.modules (hence why the behaviour would be the same if we imported using `import foo.b` as `from foo import b`).

I personally prefer to use the metapath instead of modifying sys.modules but I agree that the given example should work when the lazy import is not in `__init__.py`. The other solution is to modify the `LazyLoader` class to explicitly add the lazy module to the package's namespace (opinions?).