python编写程序，模仿猜拳游戏，要求输入两个用户的不同手型，判断输赢后输出。

在Python中，你可以创建一个简单的猜拳游戏（Rock-Paper-Scissors），通常玩家可以选择石头（Rock）、纸（Paper）或剪刀（Scissors）。下面是编写这个游戏的一个基本步骤：

import random

def user_choice():
    choices = ["rock", "paper", "scissors"]
    while True:
        user_input = input("请输入你的选择 (rock/paper/scissors)，或者输入 'quit' 退出游戏：")
        if user_input.lower() in choices or user_input.lower() == "quit":
            return user_input.lower()
        else:
            print("无效的选择，请重新输入.")

def computer_choice():
    return random.choice(["rock", "paper", "scissors"])

def game_round(user, computer):
    if user == computer:
        return "平局！"
    elif (user == "rock" and computer == "scissors") or \
         (user == "paper" and computer == "rock") or \
         (user == "scissors" and computer == "paper"):
        return f"{user} 赢了！"
    else:
        return f"{computer} 赢了！"

while True:
    user_selection = user_choice()
    if user_selection == "quit":
        break
    computer_selection = computer_choice()
    result = game_round(user_selection, computer_selection)
    print(result)

print("游戏结束！")