@Override
    public int hashCode() {
        return Objects.hash(targetMap);
    }
@Test
    void testHashCode() {
        Map<String, Object> map = new LowerCaseLinkHashMap<>(lowerCaseLinkHashMap);
        Assertions.assertEquals(lowerCaseLinkHashMap.hashCode(), map.hashCode());
        map.put("equals", "equals2");
        Assertions.assertNotEquals(lowerCaseLinkHashMap.hashCode(), map.hashCode());
    }