def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def usage_iter(root):
    root = os.path.abspath(root)
    root_size = get_folder_size(root)
    root_string = "{0}\n{1}".format(root, root_size)
    yield [root_string, None, root_size]