### Question:
Tuple6 extends Tuple5<T1, T2, T3, T4, T5> implements Tuple { public static <T1, T2, T3, T4, T5, T6> Tuple6<T1, T2, T3, T4, T5, T6> of(T1 a, T2 b, T3 c, T4 d, T5 e, T6 f) { return new Tuple6<>(a, b, c, d, e, f); } Tuple6(T1 a, T2 b, T3 c, T4 d, T5 e, T6 f); static Tuple6<T1, T2, T3, T4, T5, T6> of(T1 a, T2 b, T3 c, T4 d, T5 e, T6 f); T6 getItem6(); @Override Tuple6<T, T2, T3, T4, T5, T6> mapItem1(Function<T1, T> mapper); @Override Tuple6<T1, T, T3, T4, T5, T6> mapItem2(Function<T2, T> mapper); @Override Tuple6<T1, T2, T, T4, T5, T6> mapItem3(Function<T3, T> mapper); @Override Tuple6<T1, T2, T3, T, T5, T6> mapItem4(Function<T4, T> mapper); @Override Tuple6<T1, T2, T3, T4, T, T6> mapItem5(Function<T5, T> mapper); Tuple6<T1, T2, T3, T4, T5, T> mapItem6(Function<T6, T> mapper); @Override Object nth(int index); @Override List<Object> asList(); @Override int size(); @Override String toString(); @Override boolean equals(Object o); @Override int hashCode();  }### Answer:
@Test public void assertNullValues() { assertThat(Tuple6.of(null, 1, 2, 3, 4, 5)).containsExactly(null, 1, 2, 3, 4, 5); assertThat(Tuple6.of(1, null, 2, 3, 4, 5)).containsExactly(1, null, 2, 3, 4, 5); assertThat(Tuple6.of(1, 2, null, 3, 4, 5)).containsExactly(1, 2, null, 3, 4, 5); assertThat(Tuple6.of(1, 2, 3, null, 4, 5)).containsExactly(1, 2, 3, null, 4, 5); assertThat(Tuple6.of(1, 2, 3, null, 4, 5)).containsExactly(1, 2, 3, null, 4, 5); assertThat(Tuple6.of(1, 2, 3, 4, null, 5)).containsExactly(1, 2, 3, 4, null, 5); assertThat(Tuple6.of(null, null, null, null, null, null)).containsExactly(null, null, null, null, null, null); }
@Test public void testEquality() { assertThat(someTuple).isEqualTo(someTuple); assertThat(someTuple).isNotEqualTo(Tuple6.of(1, 2, 4, 5, 6, 10)); assertThat(someTuple).isNotEqualTo("not a tuple"); assertThat(someTuple).isEqualTo(Tuple6.of(1, 2, 3, 4, 5, 6)); }