Python - urlwatch, hooks

I use urlwatch to monitor several urls 1 of them being a zip file. I find that if I watch the zip file directly and changes occur it does in fact report the change but it also dumps the bin into the body of the email. This can cause huge emails which I am trying to avoid. What I would like to do is use a hooks file which if the zip file has changed it simply emails mails me "Zip file has changed" instead of the entirety of the contents.

If any one has any clue on how to make this happen, that would be greatly appreciated.