我这样定义一个“扑克牌类”，有问题吗？

import random
class deck:
    def __init__(self):
        suits=['♦','♣','♥','♠']
        ranks=['2','3','4','5','6','7','8','9','10','J','Q','K','A']
        self.deck=[]
        for rank in ranks:
            for suit in suits:
                card=suit+rank
                self.deck+=[card]

    def clear(self):
        n=len(self.deck)
        for i in range(n):
            r=random.randrange(i,n)
            self.deck[i],self.deck[r]=self.deck[r],self.deck[i]

    def play(self):
        self.clear
        for s in self.deck:
            print(s)

def main():
    deck1=deck()
    deck1.play

if __name__=='__main__':main()