@Test
void testCreateWithNewKeys() {

    ImmutableMap<Integer, Integer> baseMap = ImmutableMap.of(
            3, 1,
            7, 2,
            14, 3,
            1, 4);
    ImmutableMap<Integer, Integer> expected = ImmutableMap.of(
            6, 1,
            14, 2,
            28, 3,
            2, 4);
    ImmutableMap<Integer, Integer> actual = ImmutableMapFactory.
            createWithNewKeys(baseMap, key -> key * 2);
    Assertions.assertEquals(expected, actual);
}