[Zope] Python Class Question

Let's say I have a class called Chicken in a file called Chicken.py Now let's say I want to add a method called getSize() to the Chicken class. It's a piece of cake to add the method in the Chicken.py file. But, is it possible to add the method to the Chicken class, but have that method in a different file, i.e. some file other than Chicken.py? Thanks, Dan