protected function getEffectiveMembership()
    {
        if (isset($this->regid) === false) {
            $this->getGroup();
        }
        if (is_null($this->regid) === true) {
            throw new \Exception('Group Id not specified');
        }
        try {
            $resp = static::getGroupConnection()->execGET(
                "$this->identifier/effective_member"
            );
        } catch (\Exception $e) {
            throw $e;
        }

        $this->effectivemembers = [];
        $this->parseMembership($resp->getData());
    }