def METHOD_NAME(
    self, b64_md5: B64MD5, size: int
) -> Tuple[FilePathStr, bool, "Opener"]:
    hex_md5 = b64_to_hex_id(b64_md5)
    path = self._obj_dir / "md5" / hex_md5[:2] / hex_md5[2:]
    return self._check_or_create(path, size)