Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Python Object-Oriented Python Dice Roller RPG Roller

How does hand not have a roll method?

Hi, I'm trying to finish this assignment, but when I run this code it says "Bummer: 'Hand' doesn't have a roll method". Am I missing something, because as far as I can tell I've defined a method called roll already.

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__(20)
hands.py
import dice

class Hand(list):
    def __init__(self, *args, **kwargs):
        super().__init__()

    def roll(self, size=2):
        for _ in range(size):
            self.append(dice.D20())      

    @property
    def total(self):
        return sum(self)

1 Answer

Steven Parker
Steven Parker
231,275 Points

You're close, but:

  • "roll" needs to be a class method
  • "roll" needs to "return" a new instance of Hand
  • you won't need to override "init"

I think you meant to say "roll" needs to be a class method, since Hand is the name of the class. I finally got it working, so thanks for the help. I learned a lot more about how class methods work while being stuck on this problem.

Steven Parker
Steven Parker
231,275 Points

Good catch, I fixed it above — happy coding!