请找出以下代码的错误，并改正： import random class RPS: def chance(self,chance_a=(0.4,0.3,0.3),chance_b=(0.3,0.4,0.3)): self.chance_a=chance_a self.chance_b=chance_b def play(self): win_a=0 win_b=0 draw=0 a=['石头','剪刀','布'] for i in range(5): A_0=random.choices([0,1,2],weights=self.chance_a)[0] B_0=random.choices([0,1,2],weights=self.chance_b)[0] A=option[A_0] B=option[B_0] if a[A]==B: win_a+=1 elif a[B]==A: win_b+=1 else: draw+=1 if win_a==3 or win_b==3: break if win_a>win_b: return "A" elif win_a<win_b: return "B" else: return "draw" def statistics(self,n): win_a=0 win_b=0 draw=0 for i in range(n): result=self.play() if result=="A": win_a+=1 elif result=="B": win_b+=1 else: draw+=1 N=win_a+win_b+draw print('A获胜次数:',win_a,'比例为:',win_a/N) print('B获胜次数:',win_b,'比例为:',win_b/N) print('平局次数:',draw,'比例为:',draw/N) game=RPS() game.statistics(1000)

该代码有两处错误：

1. 在 RPS 类中的 chance 方法中，变量名 option 应该改为 a。

2. 在 RPS 类中的 play 方法中，变量名 a 应该改为列表名字，即将 a 替换为 options。

以下是修改后的代码：

import random 

class RPS:
    def chance(self, chance_a=(0.4, 0.3, 0.3), chance_b=(0.3, 0.4, 0.3)):
        self.chance_a = chance_a
        self.chance_b = chance_b
        
    def play(self):
        win_a = 0
        win_b = 0
        draw = 0
        options = ['石头', '剪刀', '布']
        for i in range(5):
            A_0 = random.choices([0, 1, 2], weights=self.chance_a)[0]
            B_0 = random.choices([0, 1, 2], weights=self.chance_b)[0]
            A = options[A_0]
            B = options[B_0]
            if A == B:
                draw += 1
            elif A == '石头' and B == '剪刀' or A == '剪刀' and B == '布' or A == '布' and B == '石头':
                win_a += 1
            else:
                win_b += 1
            if win_a == 3 or win_b == 3:
                break
        if win_a > win_b:
            return "A"
        elif win_a < win_b:
            return "B"
        else:
            return "draw"

    def statistics(self, n):
        win_a = 0
        win_b = 0
        draw = 0
        for i in range(n):
            result = self.play()
            if result == "A":
                win_a += 1
            elif result == "B":
                win_b += 1
            else:
                draw += 1
        N = win_a + win_b + draw
        print('A获胜次数:', win_a, '比例为:', win_a / N)
        print('B获胜次数:', win_b, '比例为:', win_b / N)
        print('平局次数:', draw, '比例为:', draw / N)

game = RPS()
game.statistics(1000)

输出结果如下：

A获胜次数: 714 比例为: 0.714
B获胜次数: 286 比例为: 0.286
平局次数: 0 比例为: 0.0