public void personCarriesThingReturnsCarriedThing()
    {
      Person person = new Person("John");
      Thing thing = new Thing("Hat");

      var item = person.CarryItem(thing);
      Assert.That(item, Is.EqualTo(thing));
    }
 public void personCarriesNullItemReturnsNull()
 {
   Person person = new Person("John");
   Assert.That(person.CarryItem(null), Is.Null);
 }