self.request = request
layout_fn = 'templates/layout.pt'

@property
def layout(self):
    macro_template = get_template(self.layout_fn)
return macro_template

@property
def logged_in_user_id(self):
    """
        Returns the ID of the current user
        """
return authenticated_userid(self.request)
How to use template inheritance with Chameleon?