codewars/courses/python_oop/descriptor/ex_2.py

class IntegerValue:
    def __set__(self, instance, value):
        print('__set__ called')

    def __get__(self, instance, owner_class):
        print('__get__ called')


class Point:
    x = IntegerValue()


def test_1():
    p = Point()
    p.x = 100   # вызывает __set__ у дескриптора
    p.x         # вызывает __get__ у дескриптора
    print(p.__dict__)
    p.__dict__['x'] = [10, 20, 30]
    print(p.__dict__)
    print(p.x)
    p.x = 200
    print(p.__dict__)

def main():
    test_1()

if __name__ == '__main__':
    main()