Can nested class be written in Python? It's like writing a class inside of another class? Are there any use cases of nested class?

Question

class Play:
    def __init__(self):
        a = 7
        b = 7
        return a + b
    class Learn:
        def __init__(self, a, b):
            self.a = a
            self.b = b
            return a - b

Python class This is just an example of how a nested class look like. I don't find how to take advantage of a nested class and nested function. Who knows what the use of nested class and function will result in? You can take your adventure in programming to try to see what a nested class might offer.