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Python Object-Oriented Python Dice Roller RPG Roller

Stuck on RPG roller challenge part 2

Hello,

I am stuck on this challenge. I think I have the codes right, but when I try to check the work I get Bummer! Can't get the length of a 'Hand'

I would like some guidance on where I am wrong. Please do not give me answers for this challenge, I would like to know and really solve this.

I would also like to know if there is any difference between these two codes

    def __init__(self, size = 0, die_class = D20):
        super().__init__()
        for _ in range(size):
            self.append(die_class())

and

    def __init__(self, size = 0, die_class = None):
        super().__init__(size = 20, die_class = D20) 

Below this line are the codes that I have written for this challenge.

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,size=20):
        super().__init__(size)
hands.py
from dice import D20

class Hand(list):

    def __init__(self, size = 0, die_class = None):
        if not die_class:
            raise ValueError("You need to have die_class")
        super().__init__(size = 20, die_class = D20) 

    @classmethod
    def roll(cls, number):
        if number > 0:
            return cls(size = 20, die_class = D20)
            number -= 1

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

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,082 Points

In both __init__ examples, super() refers to the parent class list. In the second example, super is passing arguments to list. The class list does not know what to do with the arguments die_class or size so nothing happens with them.

    def __init__(self, size = 0, die_class = None):
        super().__init__(size = 20, die_class = D20)

So use the first example to initiate the Hand with die_class instances.

You roll method is SO close. The size argument should be 2 not 20.

Also, the number decrement is unused and not reachable after the return statement.