CExtranet::IsExtranetSocNetGroup

static function IsExtranetSocNetGroup($groupID): bool
{
	if (!Loader::includeModule('socialnetwork'))
	{
		return false;
	}

	$extranet_site_id = self::GetExtranetSiteID();
	$arGroupSites = [];

	$rsGroupSite = CSocNetGroup::GetSite($groupID);
	while($arGroupSite = $rsGroupSite->Fetch())
	{
		$arGroupSites[] = $arGroupSite["LID"];
	}

	return (in_array($extranet_site_id, $arGroupSites, true));
}