@Test
    public void testDeleteElement() throws Exception {
        List<String> list = new List<>();
        list.addToEnd("test1", 1);
        list.addToEnd("test2", 3);
        for (String current : list) {
            assertTrue(list.exist(current));
        }
        list.deleteElement("test2");
        list.deleteElement("test1");
        for (String current : list) {
            assertFalse(list.exist(current));
        }
    }