I have question about DEFINE CLASS in DEFINE CLASS.

I have seen this code in “Special Edition Using Visual FoxPro 6.0”.
It is Listing 15.2. in Chapter 15.

This code is exported from Class Browser.
I am confused how in this code exist DEFINE CLASS in DEFINE CLASS?

I have ADD OBJECTS in my Container Class but there is no DEFINE CLASS of those class from which I have added objects. I must first to create them separately and then add them to my container.

My question is how to (using Class Designer) add objects with first DEFINE CLASS (not adding from separately defined class in class library)?