[Zope] Adding DTML Templates to ZClass instances

I would like to have an option when creating an instance of a folderish object to have a "index_html" template automatically added to the new object once it is created. I have the template for the inserted index_html sitting in my root directory of Zope. How can I tell the constructor method to add this template as a DTML Method (template_dtml) to the just created instance and rename it to "index_html"? This I cannot find documented anywhere. What I'm trying to do is practically identical to the option available when adding a standard DTML Document/Method from the management interface. Thanks in advance, Eron