how does this code work..?

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)

Answer 1

An object (say, for example, "obj") of class Vector2D has 2 components, namely obj.x and obj.y –that's how you defined the __init__ method. When you add 2 Vector2D objects, using "+", then the __add__ method is automatically called.