Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Python Object-Oriented Python Dice Roller RPG Roller

Deniz Kahriman
Deniz Kahriman
8,538 Points
Posted by Deniz Kahriman
Deniz Kahriman
8,538 Points

What am I doing wrong here? Can you please help? Thanks!!!

Now update Hand in hands.py. I'm going to use code similar to Hand.roll(2) and I want to get back an instance of Hand with two D20s rolled in it. I should then be able to call .total on the instance to get the total of the two dice.

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

    @classmethod
    def roll(cls, size=2)
        return cls.size

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

4 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

You're pretty close, but I see a few issues:

  • you forgot the colon (":") at the end of the definition line for the roll method
  • cls represents the class itself (not an instance), so you can't take the size property of it
  • you want to return an instance of the class, so you'll need to invoke it (with parentheses after the name)
  • remember to pass the size argument when you create the instance
Deniz Kahriman
Deniz Kahriman
8,538 Points
Deniz Kahriman
Deniz Kahriman
8,538 Points

Thanks, Steven!! Sorry, had to repost the changes I made because there was a typo. I'm stuck again as I don't know what needs to be added to make the code work. Can you please take a look? Thank you again!

from dice import D20:

class Hand(list):

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

    @classmethod
    def roll(cls, size=2):
        return cls(size)

    @property
    def total(self):
        return sum(self)
Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

Somehow, you stuck a stray colon on the end of your import line. Otherwise, I think you've got it. :+1:

Deniz Kahriman
Deniz Kahriman
8,538 Points
Deniz Kahriman
Deniz Kahriman
8,538 Points

Ahhhh... thanks, Steven!! :)

Adrian Torrente Tenreiro
Adrian Torrente Tenreiro
12,540 Points
Adrian Torrente Tenreiro
Adrian Torrente Tenreiro
12,540 Points

Deniz Kahriman could you comment the code pls? im still really stuck on this

Teeyai Muenchana
Teeyai Muenchana
5,916 Points
Teeyai Muenchana
Teeyai Muenchana
5,916 Points

from dice import D20

class Hand(list):

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

@classmethod
def roll(cls, size=2):
    return cls(size)

@property
def total(self):
    return sum(self)
Trenton Spears
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Trenton Spears
Python Development Techdegree Graduate 16,969 Points
Trenton Spears
.a{fill-rule:evenodd;}techdegree seal-36
Trenton Spears
Python Development Techdegree Graduate 16,969 Points

from dice import D20

class Hand(list):

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

@classmethod
def roll(cls, size=2):
    return cls(size)

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

Thanks to Deniz Kahriman and Steven Parker on this one, this one actually works..Thanks guys!