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Python Object-Oriented Python Dice Roller RPG Roller

Carlin Ng
Carlin Ng
2,492 Points

Bummer: Got the wrong length for a `Hand`,

Hi. I'm wondering why I keep getting the error Bummer: Got the wrong length for a Hand, what am I doing wrong here?

And also if defining dice_class absolutely necessary in the init method? @K

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
from dice import D20

class Hand(list):
    def __init__(self, rolls):
        self.outs = []
        super().__init__()
        for _ in range(rolls):
            self.outs.append(int(D20()))


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

    @classmethod
    def roll(cls, rolls):
        return cls(rolls)  

Kenneth Love

2 Answers

Steven Parker
Steven Parker
231,269 Points

The "roll" method must take an argument for the number of dice to roll, but the constructor should not. The challenge will expect to still be able to create a "Hand" instance without an argument.

You can still override "__init__" if you don't change the calling signature, but it's not necessary. Depending on how you implement "roll", no other changes need be made.

Hi Steven, in your Sep 1 answer, to what do you refer when you say constructor? I thought constructor was the roll method. Thank you.

Steven Parker
Steven Parker
231,269 Points

The "constructor" is the "__init__" method.