[Zope] How Do I manage_AddProduct for ZPT?

[beno]

I'm trying either of these expressions:

<p tal:replace="structure 
python:here.manage_addProduct['PageTemplates'].manage_addPageTemplate(id, 
title='testing', text=None, REQUEST=None)" />
--or--
<p tal:replace="structure 
python:path(manage_addProduct['PageTemplates'].manage_addPageTemplate(id, 
title='testing', text=None, REQUEST=None))" />

but the error says *manage_addProduct is not defined*. What am I missing?
TIA,
beno