我正试着用python做一个石头布剪刀游戏，但我得到的un缩进不匹配任何外部缩进杠杆错误。

import random

def get_computer_choice():
    choices = ['石头', '布', '剪刀']
    return random.choice(choices)

def determine_winner(player_choice, computer_choice):
    if player_choice == computer_choice:
        return "平局"
    elif (player_choice == '石头' and computer_choice == '剪刀') or \
         (player_choice == '布' and computer_choice == '石头') or \
         (player_choice == '剪刀' and computer_choice == '布'):
        return "你赢了"
    else:
        return "电脑赢了"

player_choice = input("请输入你的选择（石头、布、剪刀）：")
computer_choice = get_computer_choice()
result = determine_winner(player_choice, computer_choice)
print("电脑选择了：", computer_choice)
print("结果：", result)