我目前正在学习python中的类继承。在下面的示例中，目标是在包含13张不同的随机卡的单手牌中移除卡对（任何两张具有相同值和颜色的卡，例如3个心形和3个菱形）。
看来错误在第127行：if match in self.cards:。即使match不在self.cards中，该语句也始终返回true。错误为ValueError: list.remove(x): x not in list。任何人都知道如何实现预期目标吗？谢谢。
ps的学习方法：如何像计算机科学家一样思考。
class Card:
"""represents a card found in a standard deck with 52 cards."""
suits = ["Clubs", "Diamonds", "Hearts", "Spades"]
ranks = ["narf", "Ace", "2", "3", "4", "5", "6", "7",
"8", "9", "10", "Jack", "Queen", "King"]
def __init__(self, suit=0, rank=0):
self.suit = suit
self.rank = rank
def __str__(self):
return (self.ranks[self.rank] + ' of ' + self.suits[self.suit])
def cmp(self, other):
if self.suit > other.suit:
return 1
if self.suit < other.suit:
return -1
if self.rank < other.rank:
return 1
if self.rank < other.rank:
return -1
return 0
def __eq__(self, other):
return self.cmp(other) == 0
def __le__(self, other):
return self.cmp(other) <= 0
def __lt__(self, other):
return self.cmp(other) < 0
def __ge__(self, other):
return self.cmp(other) >= 0
def __gt__(self, other):
return self.cmp(other) > 0
def __ne__(self, other):
return self.cmp(other) != 0
class Deck:
"""Contains a list of cards as attribute and generates the 52 cards"""
def __init__(self):
self.cards = []
for suit in range(4):
for rank in range(1, 14):
self.cards.append(Card(suit, rank))
def __str__(self):
s = ""
for i in range(len(self.cards)):
s = s + " " * i + str(self.cards[i]) + "\n"
return s
def print_deck(self):
for card in self.cards:
print(card)
def shuffle(self):
"""shuffles the deck of cards randomly."""
import random
rng = random.Random()
rng.shuffle(self.cards)
def remove(self, card):
"""Removes a single specified card from the deck."""
if card in self.cards:
self.cards.remove(card)
return True
else:
return False
def pop(self):
"""Select a single card from the deck"""
return self.cards.pop()
def is_empty(self):
if self.cards == []:
return True
return False
def deal(self, hands, num_cards=52):
"""Deals cards from the deck to a list of hands.
If number of card to deal is not specified, the entire deck is dealt."""
for i in range(num_cards):
if self.cards == []:
break
card = self.pop()
hand = hands[i % len(hands)]
hand.add(card)
class Hand(Deck):
def __init__(self, name=''):
Deck.__init__(self)
self.cards = []
self.name = name
def __str__(self):
string = "The Hand " + self.name
if self.is_empty():
string += 'is empty.\n'
else:
string += ' contains:\n'
return string + Deck.__str__(self)
def add(self, card):
self.cards.append(card)
class CardGame:
def __init__(self):
self.deck = Deck()
self.deck.shuffle()
class OldMaidHand(Hand):
"""Creates a hand for a single player to play a game of Old Maid."""
def remove_matches(self):
cards = self.cards[:]
for card in cards:
match = Card(3 - card.suit, card.rank)
if match in self.cards:
self.cards.remove(card)
self.cards.remove(match)
print('Hand {0} removed {1} and {2}.'
.format(self.name, card, match))
game = CardGame()
player1 = OldMaidHand('test')
game.deck.deal([player1], 13)
player1.print_deck()
player1.remove_matches()