[Zope] Product event when zope restarts

Hello all! I have been developing a Zope Product that basically reads in a file and shows it in zope. The problem is that when the file is updated in file system, that is not updated in zope. I do not want it to read the file every time it is accessed in zope. Refreshing it every time the zope restarts seems to be the solution. So I was wondering if there is a function that will be executed when zope restarts. Thanx.