Should a class be an attribute for another class if all I need is the data from it?

Question

Title sucks, I know, but I'm having trouble describing my question.

Say I have a class Three_Eyed_Robot that sees the world in RGB through three eyes. Lets call them Red_Eye, Green_Eye, Blue_Eye, each of which are classes of their own that load a deep learning model for vision, then store the data they see.

My question is this: should I merely have a class attribute for Three_Eyed_Robot called red_data and instantiate the Red_Eye class in a method that sets red_data, or instead have Red_Eye be an attribute of Three_Eye_Robot and use the data by calling Three_Eyed_Robot.Red_Eye.red_data?

Edit: clearer wording.

Answer 1

Design (at least in OO) always depends on behavior.

So it depends on what the Three_Eyed_Robot does. I.e. what methods it has and what it needs to fulfill those methods. If it only needs the "data", then yes, it should only have the data.

In general, you should try to avoid getting data from other objects. It makes the design less maintainable, since things get used elsewhere makes seeing what happens harder.