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Python Object-Oriented Python Dice Roller RPG Roller

Ron Tovbin
seal-mask
.a{fill-rule:evenodd;}techdegree
Ron Tovbin
Python Web Development Techdegree Student 6,268 Points

Not sure why this is not working. Thanks in advance.

thanks.

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 __init__(self):
         super().__init__()
    def roll(self,numrolls):
        for _ in range(numrolls):
            self.append(D20())
    @property
    def length(self):
        return  len(self)
    @property
    def total(self):
        return sum(self)

2 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,457 Points

You are on the right path. One hint is in how the method will be called. By using Hand.roll(2), "Hand" is capitalized, implying this will be a classmethod and not an standard instance method.

In a classmethod, the self, in this case, would be the actual class Hand, enabling an instance to be generated using self() which will create a new base instance. Use append as you have to add each D20 to the new instance. Finally return this new instance. A return is needed to send back the newly created instance.

Also note, typically in a classmethod, "cls" is used instead of "self" to represent the class involved instead of the instance of the class.

Post back if you need more help. Good luck!!

Ron Tovbin
seal-mask
.a{fill-rule:evenodd;}techdegree
Ron Tovbin
Python Web Development Techdegree Student 6,268 Points

That helped a lot. so thank you. getting there but still stuck.

class Hand(list):
    def __init__(self):
        super().__init__()
    @property
    def total(self):
        return sum(self)
    @classmethod
    def roll(cls, numrolls=2):
        hand = cls()
        for _ in numrolls:
            hand.append(D20())
        return hand
    @property
    def length(self):
        return len(self)
Chris Freeman
Chris Freeman
Treehouse Moderator 68,457 Points

The range was dropped from the for loop. Also the length property seems to mess up the checker. Removing it pass the challenge.