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Start your free trialBrad Givens
6,621 PointsRPG challenge 2/2. Hands.total not correct value
Keep getting error saying the total value is not correct but I don't see anything that is jumping out at me for being incorrect.
Any thoughts?
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)
from dice import D20
class Hand(list):
def __init__(self, dice, *args, **kwargs):
super().__init__(dice)
@classmethod
def roll(cls, num):
result = []
for _ in range(num):
result.append(D20())
return cls(result)
@property
def total(self):
return sum(self)
1 Answer
Jay Reyes
Python Web Development Techdegree Student 15,937 PointsThe thing is we don't need to override __init__
-- at least for now.
It turns out, in the scope of the classmethod, we can call cls()
(which Kenneth glosses over, I think). Based on this article, cls()
will construct class Hand
and call the __init__
function.
So the only piece of code you need to add is:
@classmethod
def roll(cls, size=0, die_type=D20):
hand = cls()
for _ in range(size):
hand.append(die_type())
return hand
The below are just my thoughts:
From a high level view, class methods are another way to run the class __init__
. I'll now view class methods as template (or constructor).
So it makes sense to name the object hand
because we are "stuffing" the class (as an "instance"...) into the class method as a list.
Now, the difference between an instance (not instance method) and a class method? Maybe an instance is the default template while class method is an alternative template.
Chris Freeman
Treehouse Moderator 68,457 PointsChris Freeman
Treehouse Moderator 68,457 PointsMoved Comment to Answer.