import  random

# 随机取0~1之间的小数

print(random.random())

# 随机取2数之间的整数

print(random.randint(10,30))

# 随机取2数之间的整数,结束值不包含在范围内

print(random.randrange(1,3))#如3不会取出

# 随机取列表的一个元素

print(random.choice([2,"xx",{"name":"jia"}]))

# 随机取列表的N个元素

print(random.sample([2,"xx",{"name":"jia"},1,4,5,7,8],3))

# 随机取2数之间的浮点型

print(random.uniform(1,9))

import sys, time,random

# 这是倒计时

def time_remain(lineTmpla, mins):

    count = 0

    mins = int(mins+1)

    while (count < mins):

        count += 1

        n = mins - count

        time.sleep(1)

        sys.stdout.write("\r" + lineTmpla+ "%3s"%n)

        sys.stdout.flush()

        # if n:

        #     print("\r" + lineTmpla+ str(n))

        if not n:

            return '\ncompleted'

# 验证码功能

def yanzhengma(q = 4):

    a= ""

    for i in range(q):

        num = random.randint(0,9)

        alf = chr(random.randint(65,90))

        alf_2 = chr(random.randint(97, 122))

        s = str(random.choice([num,alf,alf_2]))

        a += s

    return a

if __name__ == '__main__':

    flg = 5

    n = input("需要几位验证码：")

    s = yanzhengma(int(n))

    print(s)

    flg_1 =True

    while flg_1:

        if flg == 0:

            time_remain("请等待：", 4)

            flg = 5

        while flg:

            y = input("\n输入验证码：")

            if y == s:

                print("通过")

                flg_1 =False

                break

            else:

                print("还剩%s次"%(flg-1))

                flg -= 1