[Zope] manage_add with results

Greetings all, I'm searching around and I'm trying to locate a hint as to how I can use: manage_addDocument(id=something, file=spiral, ...) where Spiral is the results of a method. I can get the contents of the method (dtml code) into the new file, but I want the resulting text that the method would generate. Can someone steer me in the right direction please? Thanks, Paz