def _get_cache_path_parts(self, link):
        # type: (Link) -> List[str]
        """Get parts of part that must be os.path.joined with cache_dir
        """

        # We want to generate an url to use as our cache key, we don't want to
        # just re-use the URL because it might have other items in the fragment
        # and we don't care about those.
        key_parts = {"url": link.url_without_fragment}
        if link.hash_name is not None and link.hash is not None:
            key_parts[link.hash_name] = link.hash
        if link.subdirectory_fragment:
            key_parts["subdirectory"] = link.subdirectory_fragment

        # Include interpreter name, major and minor version in cache key
        # to cope with ill-behaved sdists that build a different wheel
        # depending on the python version their setup.py is being run on,
        # and don't encode the difference in compatibility tags.
        # https://github.com/pypa/pip/issues/7296
        key_parts["interpreter_name"] = interpreter_name()
        key_parts["interpreter_version"] = interpreter_version()

        # Encode our key url with sha224, we'll use this because it has similar
        # security properties to sha256, but with a shorter total output (and
        # thus less secure). However the differences don't make a lot of
        # difference for our use case here.
        hashed = _hash_dict(key_parts)

        # We want to nest the directories some to prevent having a ton of top
        # level directories where we might run out of sub directories on some
        # FS.
        parts = [hashed[:2], hashed[2:4], hashed[4:6], hashed[6:]]

        return parts
Get parts of part that must be os.path.joined with cache_dir
        
product/gradle-plugin/src/main/python/pip/_internal/cache.py