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Start your free trialrtkacddqbo
9,662 PointsNot sure how to solve this! Creating Roll method inside Hand class
I've looked at other questions on this but still haven't managed to understand this challenge nor get the right code. This has been the first challenge to really stop me in my tracks - I understand what he's asking but I don't get the logic of how to implement it: "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. I'll leave the implementation of all of that up to you. I don't care how you do it, I only care that it works."
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)
class Hand(list):
def __init__(self, sides, die_class=None, *args, **kwargs):
if not die_class:
raise ValueError("Need a die class")
for _ in sides:
self.append(die_class)
@classmethod
def roll(cls, size):
hand = Hand(size, D20)
return hand
@property
def total(self):
return sum(self)
1 Answer
Chris Freeman
Treehouse Moderator 68,441 PointsYou have the overall approach correct. The follow corrections are needed
- add missing import in
hands.py
:from dice import D20
- In
__init__
, callsuper().__init__()
to fully initialize the list - Use
range(sides)
when looping to append die._ in sides
returns "'int' object is not iterable" - Use parens when calling
die_class()
to generate instances, otherwise it's just the class type, not an instance - In
roll
usecls
passed in for class call:cls(size)
vsHand(size)
, and usedie_class
key_word argument
Post back if you have more questions. Good Luck!!
rtkacddqbo
9,662 PointsThanks for the help! I adjusted the code with your comments and it worked.
Alex Moats
4,535 PointsAlex Moats
4,535 PointsI'm currently stuck about a half step ahead on this challenge but what it looks like is you want to specify your class inputs and return cls to Hand
You may also want to specify a default value for sides in your hands.py init method
def __init__(self, sides=0, die_class=None, *args, **kwargs):