# Learn Special Methods by Building a Vector Space - Step 26

### Tell us what’s happening:

``````import math

class R2Vector:
def __init__(self, *, x, y):
self.x = x
self.y = y

def __str__(self):
return str(tuple((getattr(self, i) for i in vars(self))))

def norm(self):
return (sum(val ** 2 for val in vars(self).values())) ** 0.5

class R3Vector(R2Vector):
def __init__(self, *, x, y, z):
super().__init__(x=x, y=y)

# User Editable Region

self.z = z

v1 = R2Vector(x=2, y=3)
v2 = R3Vector(x=2, y=2, z=3)

print(f'v1 = {v1.__str__()}')
print(f'v2 = {v2.__str__()}')

# User Editable Region

``````

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36`

### Challenge Information:

Learn Special Methods by Building a Vector Space - Step 26

What is the `__str__` method and how is it used?

Why did we implement the `__str__` method, what was the purpose?

It is used to give a string representation of an object and here the purpose was to show the vector.

And in step 10, how did we use the `__str__` method? It was a while ago:
https://www.freecodecamp.org/learn/scientific-computing-with-python/learn-special-methods-by-building-a-vector-space/step-10

ah, that’s right, I don’t need to use the . call to the str, brainfart xd thank you!

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