Need help

Question

class Vector2D:
def __init__(self, x, y):
self.x = x
self.y = y
def __add__(self, other):
return Vector2D(self.x + other.x, self.y + other.y)

first = Vector2D(5, 7)
second = Vector2D(3, 9)
result = first + second
print(result.x)
print(result.y)
here what confuse me is how come the value of-other.x is 3.
and the the value of other.y is 9.

Answer 1

because the line
result = first + second it's the same with
result = first.__add__(second)
in python self parameter is the calling object here is first, so other parameter is second in this case