@Test
 public void testContainsInstanceWithInstancesThatAreEqualButDistinct() throws Exception {
   List<Instance> list = new ArrayList<>();
   list.add(new Instance("fiona"));
   assertFalse(
       "Must return false if instance is not in the supplied Collection argument",
       CollectionUtils.containsInstance(list, new Instance("fiona")));
 }
 @Test
 public void testContainsInstanceWithNullInstance() throws Exception {
   List<Instance> list = new ArrayList<>();
   list.add(new Instance("apple"));
   list.add(new Instance("fiona"));
   assertFalse(
       "Must return false if null instance is supplied",
       CollectionUtils.containsInstance(list, null));
 }
 @Test
 public void testContainsInstanceWithSameInstance() throws Exception {
   List<Instance> list = new ArrayList<>();
   list.add(new Instance("apple"));
   Instance instance = new Instance("fiona");
   list.add(instance);
   assertTrue(
       "Must return true if instance is in the supplied Collection argument",
       CollectionUtils.containsInstance(list, instance));
 }
 @Test
 public void testContainsInstanceWithNullCollection() throws Exception {
   assertFalse(
       "Must return false if supplied Collection argument is null",
       CollectionUtils.containsInstance(null, this));
 }