'Check whether this item belongs to the requested page (request).
If this check returns False, then the item will be deactivated
entirely, i.e. no further checks will be run and the renderer
will never be called.
@param request: the request object (defaults to current.request)'

def check_active(self, request=None):

    c = self.get('controller')
    if c:
        return current.deployment_settings.has_module(c)
    return True
    if (request is None):
        request = current.request
    parent = self.parent
    if (parent is not None):
        return parent.check_active(request)
    elif self.mandatory:
        return True
    elif self.match(request):
        return True
    return False
