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Python Object-Oriented Python Dice Roller RPG Roller

Ekata Singh
Ekata Singh
2,872 Points

Cant get the length of hand

I have coded as per the requirements specified in the question and it seems to work perfectly on my local IDE. Can anybody suggest why am i getting this error?

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):

    def roll(self,dice,dice_class=D20):

        for _ in list(range(dice)):
            self.append(D20())
        return self


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

1 Answer

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,716 Points

The automated grader calls Hand.roll() to instantiate during testing-- rather than instantiating Hand() explicitly. So you need to define roll() as a @classmethod.

Furthermore...

Once roll becomes a class method, you will get some different errors with your code. This is easily fixed by moving all the initialization code (including the loop from roll) into the "dunder init" function of Hand.

I hope this helps!

Ekata Singh
Ekata Singh
2,872 Points

I changed roll to a class method and it worked! Thanks Jeff :)