def save(self):
        tmp_path = self.path + '.tmp'
        with open(tmp_path, 'w') as f:
            f.write(json.dumps(self.body_labels.items()))
        os.rename(tmp_path, self.path)
def insert(root, key):
    left, right = split(root, key)
    return merge(merge(left, Treap(key)), right)