'label of set', * 'entries' => * [ * 'label-of-entry' => 'value' * ] * ] * 1: [ * 'label' => 'label of another set', * 'entries' => * [ * 'label-of-entry' => 'value' * ] * ] * * * @param array $data * * @return array */ public function multiSet(array $data): array; }