public void TestPersonPetStatic1()
 {
     Person p1 = new Person();
     Pet t1 = new Pet();
     t1.Owner = p1;
     Assert.AreEqual(t1.Owner, p1);
     Assert.IsTrue(p1.Pets.Contains(t1));
 }
 public void TestStudentPetStatic2()
 {
     Student s1 = new Student();
     Pet t1 = new Pet();
     s1.Pets.Add(t1);
     Assert.AreEqual(t1.Owner, s1);
     Assert.IsTrue(s1.Pets.Contains(t1));
 }