Imagine I have a python extension, with zope id pyFetch def Fetch (self, href): ... I want to call this in a manner similar to: <!--#let call_method="'pyFetch'"--> <!--#in sql-method-returns-href--> <!--#var "_[call_method]( href )"--> <!--#/in--> <!--#/let--> But I get an error: Error Type: TypeError Error Value: not enough arguments; expected 2, got 0 So it seems to evaluate and call the extension without adding the parameters. I guess I need something like lambda in python. Can anyone help me please? Thanks, Glenn