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Python Object-Oriented Python Dice Roller RPG Roller

Andrei Oprescu
Andrei Oprescu
9,547 Points

Can't understand how to do this challange

So I am doing a challenge and I am given this question:

Now update Hand in hands.py. I'm going to use code similar to Hand.roll(2) and I want to get back an instance of Hand with two D20s rolled in it. I should then be able to call .total on the instance to get the total of the two dice.

I'll leave the implementation of all of that up to you. I don't care how you do it, I only care that it works.

And my code is at the bottom of the comment.

Can someone please tell me what i did wrong and How I can complete this challenge?

Thanks!

dice.py
import random


class Die:
    def __init__(self, sides=2):
        if sides < 2:
            raise ValueError("Can't have fewer than two sides")
        self.sides = sides
        self.value = random.randint(1, sides)

    def __int__(self):
        return self.value

    def __add__(self, other):
        return int(self) + other

    def __radd__(self, other):
        return self + other

class D20(Die):
    def __init__(self):
        super().__init__(sides=20)
hands.py
from dice import D20
class Hand(list):
    @property
    def total(self):
        return sum(self)

    def roll(self, rolls):
        from _ in range(rolls):
            self.append(int(D20.value))

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points

You are on the right path. Three items need correcting:

  • To be called as Hand.roll(2), the method roll needs to be decorated as a @classmethod
  • As a classmethod, there is no instance yet, so create one using inst = self() since self points to the class when decorated as a classmethod
  • The instance created needs to be returned! So include a return inst in the method

Not syntactically wrong, but a style norm is to use cls instead of self in the classmethod code.

Post back if you have more questions. Good luck!