用Python怎么写定时器

from threading import Timer

t = Timer(interval, function, args=None, kwargs=None)

# interval 设置的时间(s)

# function 要执行的任务

# args，kwargs 传入的参数

t.start()  # 开启定时器

t.cancel()  # 取消定时器

import time

from threading import Timer

def task(name):

    print('%s starts time: %s'%(name, time.ctime()))

t = Timer(3,task,args=('nick',))

t.start()

print('end time:',time.ctime())  # 开启定时器后不影响主线程执行，所以先打印

-------------------------------------------------------------------------------

end time: Wed Aug  7 21:14:51 2019

nick starts time: Wed Aug  7 21:14:54 2019

import random

from threading import Timer

# 定义Code类

class Code:

    # 初始化时调用缓存

    def __init__(self):

        self.make_cache()

    def make_cache(self, interval=60):

        # 先生成一个验证码

        self.cache = self.make_code()

        print(self.cache)

        # 开启定时器，60s后重新生成验证码

        self.t = Timer(interval, self.make_cache)

        self.t.start()

    # 随机生成4位数验证码

    def make_code(self, n=4):

        res = ''

        for i in range(n):

            s1 = str(random.randint(0, 9))

            s2 = chr(random.randint(65, 90))

            res += random.choice([s1, s2])

        return res

    # 验证验证码

    def check(self):

        while True:

            code = input('请输入验证码(不区分大小写)：').strip()

            if code.upper() == self.cache:

                print('验证码输入正确')

                # 正确输入验证码后，取消定时器任务

                self.t.cancel()

                break

obj = Code()

obj.check()