Find subpackages of a namespace package in a distribution

find_subpackage.py

import importlib

def find_subpackage(dist: str, ns_name: str):
    """Finds subpackages of a namespace package
    
    Within a distribution `dist`, given a known toplevel namespace package `ns_name`,
    this finds all 2 level deep package:
    
    >>> list(find_subpackage("jaraco-classes", "jaraco"))
    ["jaraco.classes"]
    """
    for f in importlib.metadata.files(dist):
        if f.suffix != ".py":
            continue
        stem = f.with_suffix("")
        if len(stem.parts) == 3 and stem.name == "__init__":
            stem = stem.parent
        if len(stem.parts) == 2:
            yield str(stem).replace("/", ".")