编写脚本。简明Python教程

###############68页，第十章，编写一个Python脚本############### #编写一个可以为所有重要文件创建备份的程序################## #！/usr/bin/python #Filename:backup_verl.py #1.The filesand directories to be backs up are specified in a list. source=[r'C:\AMDs'] #2.The backup must be stored in am ain backup directory target_dir=r'C:\Anyos' #3.The filesare backed up in to a zip file. #4.The name of the zip arch live is the current date and time target =target_dir+time.strftime('%Y%m%d%H%M%S')+'.zip' #5.we use the zip command(in Unix/Linux)to put the files in a zip archive zip_comand="zip-qr'%s'%s"%(target,''.join(source)) #run the backup if os.system(zip_command)==0: print'Successfulbackuo to',target else: print'Backup FA ILED' 2.7.14运行后出现错误如下 = RESTART: C:/Users/john/Desktop/105.py/68页，第十章，编写一个Python脚本.py = Traceback (most recent call last): File "C:/Users/john/Desktop/105.py/68页，第十章，编写一个Python脚本.py", line 13, in <module> target =target_dir+time.strftime('%Y%m%d%H%M%S')+'.zip' NameError: name 'time' is not defined >>> 可是明明简明Python教程里面也是这样写的。 望指正