old_f_name = input(“请输入备份的文件路径:”) 
old_f = open(old_f_name, “r”)

new_f_name = “[复件]” + old_f_name 
 123.txt -> 123[复件].txt 123 + “[复件]” + .txt 
 index = old_f_name.rfind(“.”) # 获取.对应的后缀 
if index >= 0: # 如果有后缀 
new_f_name = old_f_name[:index] + “[复件]” + old_f_name[index:] 
 else: # 如果没有后缀 
new_f_name = old_f_name + “[复件]” 
new_f = open(new_f_name, “w”)

import os
import time
source = ['D:\\MyDrivers\hotfix']  #这里可以用自然字符串表示r'，因为windows下的分隔符
与python的有冲突，所以需要转义字符\
# 2. 备份文件到目标路径
target_dir = 'F:\\DMDownLoad\\' #这里的末尾一定不要丢分隔符，否者创建的文件会在F:目录下，
而不会在DMDownload目录下
# 3. The files are backed up into a zip file.
# 4. The current day is the name of the subdirectory in the main directory
today = target_dir + time.strftime('%Y%m%d') #time.strftime表示对当前时间的调用，括号内为参数设定
# The current time is the name of the zip archive
now = time.strftime('%H%M%S')
# Take a comment from the user to create the name of the zip file
comment = raw_input('Enter a comment -->')
if len(comment)==0: 
  target = today+os.sep+now+'.zip' 
#os.sep表示目录符号，windows下是\\，linux下是/,mac下是：，这里为了保证移植性，
所以os.sep会根据系统给出分隔符
else:
  target = today+os.sep+now+'_'+\
       comment.replace(' ','_')+'.zip'
  # Notice the backslash!
# Create the subdirectory if it isn't already there
if not os.path.exists(today):
  os.mkdir(today) # make directory
  print('Successfully created directory', today)
# 5. 用winrar的rar命令压缩文件，但首先要安装有winrar且设置winrar到环境变量的路径path中
zip_command = "rar a %s %s" %(target,''.join(source))
#这行命令之前的所有target  、target_dir、today这些都是字符串，只有在
这个命令和os.makedir中才是真正的表示路径
# Run the backup
#设置winrar到path环境中，这里已经手动添加了，如果没有去掉#号
#os.system('set Path=%Path%;C:\Program Files\WinRAR')
if os.system(zip_command)==0:
  print'Successful backup to', target
else:
  print'Backup FAILED'