Help regarding Python backup script.

I am a newbie and currently learning python. I use a tutorial called "A Byte Of Python" and there I encountered a little problem with an example in the tutorial. It seems as he who wrote this tutorial are running on Linux and I am running on Windows. This is the code that he wrote(Swaroop C H):

import os
import time

# 1. The files and directories to be backed up are specified in a list.
source = ['/home/swaroop/byte', '/home/swaroop/bin']
# If you are using Windows, use source = [r'C:\Documents', r'D:\Work'] or something like that

# 2. The backup must be stored in a main backup directory
target_dir = '/mnt/e/backup/' # Remember to change this to what you will be using

# 3. The files are backed up into a zip file.
# 4. The name of the zip archive 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_command = "zip -qr '%s' %s" % (target, ' '.join(source))

# Run the backup
if os.system(zip_command) == 0:
print 'Successful backup to', target
else:
print 'Backup FAILED'
------------------------------------------------------------------------

as you can see this is a backup script who copies the the targeted files into another directory and compress them to Zip Files. My dilemma is that I cant find the windows command for compressing Zip files like they
have in Linux/Unix, can anyone help me?