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Python Object-Oriented Python Dice Roller RPG Roller

Hi There, I'm stuck on the RPG roller challenge Task 2 of 2. Does anybody have the answer?

My code works when I use Pycharm on my computer but doesn't pass the online check, does anybody know why?

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

class Hand(list):

    def __init__(self):
        super().__init__()

    def roll(self, NumberOfRolls):
        for rolls in range(NumberOfRolls):
            self.append(int(D20()))

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

Hand = Hand()

2 Answers

Steven Parker
Steven Parker
230,995 Points

Here's a few hints:

  • since the method will be called directly on the class, it won't have a "self"
  • you might want to implement "roll" as a class method
  • the "roll" method above returns nothing, but it is expected to return a new instance
  • it's not necessary to override "__init__"

Hi Steven - can you explain why in this task the "Roll" method should be a class method?

Steven Parker
Steven Parker
230,995 Points

The challenge showed an example of how the method would be called directly on "Hand" (the class itself) instead of on an instance. So for that to work, it needs to be a class method.

Good answer, thanks!