Can you give some examples of replacing OO with dicts and lists? I've made classes or structs to make it easier to manage what a few associated lists/dicts were

Can you give some examples of replacing OO with dicts and lists? I've made classes or structs to make it easier to manage what a few associated lists/dicts were representing, but I'm not sure I've done the opposite. Maybe using lambdas instead of subclasses?