单线程

#单线程，"说"了再"写"
 from time import sleep,ctime
 #s说
 def talk():
     print('start talk:%r'%ctime())
     sleep(2)
 #写
 def write():
     print('start write:%r'%ctime())
     sleep(2)
 if __name__=="__main__":
     talk()
     write()
     print('all end ! %r'%ctime())