import os
import time
import winsound
iplist = list()
ip = 'www.baidu.com'
while(1):
    backinfo = os.system('ping -n 1 %s'%ip) # 实现pingIP地址的功能，-c1指发送报文一次，-w1指等待1秒
    time.sleep(1)
    if backinfo:
        print('网络不通')
    else:
        duration = 1500  # millisecond
        freq = 440  # Hz
        winsound.Beep(freq, duration)
    print ('backinfo',backinfo)