Product::getIBlockBySectionId

protected function getIBlockBySectionId($id): int
{
	$section = CIBlockSection::GetList(
		[],
		[
			'ID' => (int)$id,
		],
		false,
		[
			'ID',
			'IBLOCK_ID',
		]
	);
	$res = $section->Fetch();
	unset($section);

	return (int)($res['IBLOCK_ID'] ?? 0);
}