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Python

I just can't figure this out, either.

Trying to get the CapitilismHand.reroll() class method to work, but it won't. Please, I really want to finish this course, and not being able to figure out the last possible moment feels like torture.

hands.py
from dice import D6


class Hand(list):
    def __init__(self, size=0, die_class=None, *args, **kwargs):
        if not die_class:
            raise ValueError("You must provide a die class")
        super().__init__()

        for _ in range(size):
            self.append(die_class())
        self.sort()

    def _by_value(self, value):
        dice = []
        for die in self:
            if die == value:
                dice.append(die)
        return dice


class CapitalismHand(Hand):
    def __init__(self):
        super().__init__(size=2, die_class=D6)

    @property
    def ones(self):
        return self._by_value(1)

    @property
    def twos(self):
        return self._by_value(2)

    @property
    def threes(self):
        return self._by_value(3)

    @property
    def fours(self):
        return self._by_value(4)

    @property
    def fives(self):
        return self._by_value(5)

    @property
    def sixes(self):
        return self._by_value(6)

    @property
    def _sets(self):
        return {
            1: len(self.ones),
            2: len(self.twos),
            3: len(self.threes),
            4: len(self.fours),
            5: len(self.fives),
            6: len(self.sixes)
        }

    @property
    def doubles(self):
        double = False
        for dicty in self._sets.items():
            if dicty[1] == 2:
                double = True
        return double

    @classmethod
    def reroll(cls, size, die_class):
        hand = []
        for _ in range(size):
            hand.append(die_class)
        return cls(hand)

3 Answers

A class method's first argument is the class the method belongs to. In this case, cls is CapitalismHand, not Hand. The reroll method should return a new instance of the CapitalismHand class, so it doesn't need any arguments.

@classmethod
def reroll(cls):
    return cls()
David Welsh
David Welsh
9,298 Points

I had a lot of issues on this as well, and was directed to this stack overflow answer which broke it down for me. At first I thought, nah, no way it's that easy. Just don't overcomplicate it. https://stackoverflow.com/questions/13260557/create-new-class-instance-from-class-method

Why is this not passing the challenge? '''Python from dice import D6

class Hand(list): def init(self, size=0, die_class=None, *args, **kwargs): if not die_class: raise ValueError("You must provide a die class") super().init()

    for _ in range(size):
        self.append(die_class())
    self.sort()

def _by_value(self, value):
    dice = []
    for die in self:
        if die == value:
            dice.append(die)
    return dice

class CapitalismHand(Hand): def init(self, *args, **kwargs): super().init(size=2, die_class=D6, *args, **kwargs)

@property
def doubles(self):
    if self[0] == self[1]:
        return True

@classmetod
def reroll(cls):
    return (cls)

@property
def ones(self):
    return self._by_value(1)

@property
def twos(self):
    return self._by_value(2)

@property
def threes(self):
    return self._by_value(3)

@property
def fours(self):
    return self._by_value(4)

@property
def fives(self):
    return self._by_value(5)

@property
def sixes(self):
    return self._by_value(6)

@property
def _sets(self):
    return {
        1: len(self.ones),
        2: len(self.twos),
        3: len(self.threes),
        4: len(self.fours),
        5: len(self.fives),
        6: len(self.sixes)
    }

'''

Steven Hender
Steven Hender
5,830 Points

The above code has a typo on the "@classmetod" line It should be "@classmethod" Note the missing "h"