python入门：最基本的用户登录用户登录，三次错误机会

#!/usr/bin/env python
# -*- coding:utf-8 -*-
#用户登录，三次错误机会
"""
导入getpass，给x赋值为1，while真，循环开始，
user的赋值等于用户输入的内容，pwd的赋值等于用户输入的内容并且不可见
如果用户输入user的赋值等于"admin"而且用户输入pwd的赋值等于"admin888"
打印"login successfully!(登陆成功！)"换行 打印"welcome!:(欢迎:)user",break跳出当前循环
否则如果x的赋值等于3，打印"Failure three times!(失败三次！)"break跳出当前循环
否则打印"login failure!There are three more chances!(登录失败！有三次机会)"
x的赋值每循环一次加1，当循环3次后就满足了x赋值为3，break跳出当前循环！
"""
import getpass
x = 1
while True:
    user = raw_input("user:")
    pwd = getpass.getpass('password:')
    if user == "admin" and pwd == "admin888":
        print("login successfully!" + "
" +"welcome!:" + user)
        break
    elif x == 3:
        print("Failure three times!")
        break
    else:
        print("login failure!There are three more chances!")
    x += 1