def iter_filth_clss():
    """Iterate over all of the filths that are included in this sub-package.
    This is a convenience method for capturing all new Filth that are added
    over time.
    """
    return iter_subclasses(
        os.path.dirname(os.path.abspath(__file__)),
        Filth,
        _is_abstract_filth,
    )