python - How to initialize a Vector instance by calling a method, defined in the same class-Vector? -

so want initialize instance ov vector class, tuple return method defined in class.

class point(object):     def __init__(self, x, y):         self.x = x         self.y = y  class vector(object):     def __init__(self, x, y):         self.x = x         self.y = y      def subtract(self, a, b):         x = a.x - b.x         y = a.y - b.y         return x, y # <-- tuple   p = point(0, -1) = point(1, 1) # here want call vector.subtract(p, i) , assign tuple vector instance 

i following vector tutorial's, in c++ , syntax there different python have no idea how can this.

why don't rewrite method

def subtract(self, a, b):     x = a.x - b.x     y = a.y - b.y     return x, y # <-- tuple 

to

def subtract(self, a, b):     x = a.x - b.x     y = a.y - b.y     return vector(x, y) # <-- tuple 

it weird declare instance method substract, more reasonable make this:

def subtract(self, b):     x = self.x - b.x     y = self.y - b.y     return vector(x, y) # <-- tuple 

so can call

a = vector(1,2) b = vector(4,1) c = a.substract(b) 

or @ least make static method removing self reference

@staticmethod def subtract(a, b):     x = a.x - b.x     y = a.y - b.y     return vector(x, y)  # <-- result new vector 

and use this

c = vector.subtract(a, b)