'Perform the checks and render this item.
@param request: the request object (defaults to current.request)'

def render(self, request=None):

    renderer = self.renderer
    output = None
    if (request is None):
        request = current.request
    if self.check_active(request):
        self.authorized = self.check_permission()
        self.selected = self.check_selected()
        cond = self.check_hook()
        if cond:
            enabled = self.check_enabled()
            if (not enabled):
                self.enabled = False
            if (renderer is not None):
                output = renderer(self)
    return output
