创建Employee和Developer接口，在Employee中添加work()方法，在Developer中添加code()方法，在Person类中实现这两个方法，输出“我在工作”和“我在编码”；修改Person类，不仅能继承Human类的吃饭eat()、走路walk()外，还可以实现Employee和Developer的接口-Create Employee and Developer interface, add work in Employee () method, add code (Developer) method, the Person class to achieve these two methods, output　I am working　and　I am in encoding　 modified Person class, not only can inherit the Human class eat (), Developer (walk), but also can achieve Employee and interface