3D vector class with inheritance from 2D vector class

[buss0140]

I am trying to make a scalar multiplication method which is the last method in the code. I am not sure why it is not working. I used "return D3Vector((self.x * num), (self.y * num), (self.z * num))" It is returning only the new x and y coordinates when I use print(v4.scalarMult(3)), for example.
Here is the full code.

import math
class Vector:
  def __init__(self, x, y):
    self.x = x
    self.y = y
  
  def get_x(self):
    return self.x
  
  def set_x(self, x):
    self.x = x
  
  def get_y(self):
    return self.y
  
  def set_y(self, y):
    self.y = y
  
  def __str__(self):
    return '(' + str(self.x) + ',' + str(self.y) + ')'
  
  def __add__(self, other):
    new_x = self.x + other.x
    new_y = self.y + other.y
    total = Vector(new_x, new_y)
    return total

  def __sub__(self, other):
    new_x = self.x - other.x
    new_y = self.y - other.y
    total = Vector(new_x, new_y)
    return total

  def __mul__(self, other):
    return (self.x * other.x) + (self.y * other.y)
  
  def __abs__(self):
    return math.sqrt((self.x**2) + (self.y**2))

  def __eq__(self, other):
    return self.x == other.x and self.y == other.y

class D3Vector(Vector):
  def __init__(self, x, y, z):
    Vector.__init__(self, x, y)
    self.z = z
  
  def __add__(self, other):
    return (self.x + other.x, self.y + other.y, self.z + other.z)
  
  def __sub__(self, other):
    return (self.x - other.x, self.y - other.y, self.z - other.z)
  
  def __mul__(self, other):
    return Vector.__mul__(self, other) + self.z * other.z
  
  def __abs__(self):
    return math.sqrt(self.x**2 + self.y**2 + self.z**2)

  def __eq__(self, other):
    return Vector.__eq__(self, other) and self.z == other.z

  def scalarMult(self, num):
    return D3Vector((self.x * num), (self.y * num), (self.z * num))


v = Vector(21, 56)
v1 = Vector(13, 24)
v2 = Vector(21, 56)
v3 = D3Vector(3, 6, 9)
v4 = D3Vector(7, 4, 8)
v5 = D3Vector(7, 4, 8)

buran write Dec-20-2020, 04:13 PM:
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