public function get_submission_group_members_who_have_not_submitted($groupid, $onlyids) {
        $instance = $this->get_instance();
        if (!$instance->teamsubmission || !$instance->requireallteammemberssubmit) {
            return array();
        }
        $members = $this->get_submission_group_members($groupid, $onlyids);

        foreach ($members as $id => $member) {
            $submission = $this->get_user_submission($member->id, false);
            if ($submission && $submission->status == ASSIGN_SUBMISSION_STATUS_SUBMITTED) {
                unset($members[$id]);
            } else {
                if ($this->is_blind_marking()) {
                    $members[$id]->alias = get_string('hiddenuser', 'assign') .
                                           $this->get_uniqueid_for_user($id);
                }
            }
        }
        return $members;
    }