[Zope] External <-> DTML Methods

Hi, Shalabh helped me a lot further, he gave me an external method which helps me on the way, however I would like to know if it's possible to write this in a DTML-method. If this isn't possible, then why isn't this possible? Here is the external method (placed in the Methods view of a class) def manage_afterAdd(self,item,container): item.myparent=container.id return Is it possible to write this in DTML? Thanks in advance, Tom.