protected function col_actions($data) {
        global $OUTPUT;

        $action = new \confirm_action(get_string('removecohortroleassignmentconfirm', 'tool_cohortroles'));
        $url = new moodle_url($this->baseurl);
        $url->params(array('removecohortroleassignment' => $data->id, 'sesskey' => sesskey()));
        $pix = new \pix_icon('t/delete', get_string('removecohortroleassignment', 'tool_cohortroles'));
        return $OUTPUT->action_link($url, '', $action, null, $pix);
    }