676315.py

import unittest
from typing import Tuple, Union, Callable

Vec2D = Tuple[int, int]
Vec2DF = Callable[[], Vec2D]


class Point:
    def __init__(self, cord: Union[Vec2D, Vec2DF]):
        self._cord = cord

    def __add__(self, rhs: 'Point') -> 'Point':
        return Point(
            lambda: (self.x + rhs.x, self.y + rhs.y)
        )

    @property
    def cord(self) -> Vec2D:
        if isinstance(self._cord, Tuple):
            return self._cord
        else:
            return self._cord()

    @property
    def x(self) -> int:
        return self.cord[0]

    @x.setter
    def x(self, value: int):
        self._cord = (value, self.y)

    @property
    def y(self) -> int:
        return self.cord[1]

    @y.setter
    def y(self, value: int):
        self._cord = (self.x, value)


class TestPoint(unittest.TestCase):
    def test(self):
        p1 = Point((1, 2))
        p2 = Point((3, 4))
        self.assertEqual(p1.x, 1)
        self.assertEqual(p1.y, 2)

        p_sum = p1 + p2
        self.assertEqual(p_sum.x, 4)
        self.assertEqual(p_sum.y, 6)
        p1.x = 10
        self.assertEqual(p_sum.x, 13)

        # chained
        p_sum2 = p_sum + p1 + p2
        self.assertEqual(p_sum2.x, p1.x*2 + p2.x*2)
        p2.x = 100
        self.assertEqual(p_sum2.x, p1.x*2 + p2.x*2)


if __name__ == "__main__":
    unittest.main()