It took me a while to realize that you do mean __init__.py running when a package imports.
But, you know, top-level code (which can do anything) runs when you import any Python module (the first time), and Python code doesn't have to be in a package to get imported. (The standard library depends on this.)
But, you know, top-level code (which can do anything) runs when you import any Python module (the first time), and Python code doesn't have to be in a package to get imported. (The standard library depends on this.)