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Python Object-Oriented Python Dice Roller RPG Roller

Viktor Kelemen
Viktor Kelemen
3,747 Points

Python Yatzy game Hand class Challenge seems right to me but getting "Bummer: Can't get the length of a `Hand`" error.

I don't see the error in my script, can someone explain the problem for me, please?

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, size):
        self.size = size
        for _ in range(size):
            self.append(int(D20()))

1 Answer

Steven Parker
Steven Parker
230,231 Points

You're getting close, here's a few hints:

  • the instructions say to return a new instance of Hand (but this code doesn't return anything)
  • they also say to roll D20's in the hand (not integers made from D20's)
  • based on how the instructions say the method will be called, it should probably be a class method
Viktor Kelemen
Viktor Kelemen
3,747 Points

Thanks, thats helped me a lot