/**
* Perform an 'item' request for the CheckfrontModule.package_category_id() category with 'packages' option set on.
*
* @param null $startDate
* @param null $endDate
* @param array $filters
* @return CheckfrontAPIPackagesResponse
*/
public function listPackages($startDate = null, $endDate = null, array $filters = array())
{
static $cache = array();
$cacheKey = md5(implode('|', array($startDate, $endDate, implode('|', $filters))));
if (!isset($cache[$cacheKey])) {
$params = self::request_params(__FUNCTION__, array('category_id' => CheckfrontModule::package_category_id(), 'packages' => true), $this->buildDates($startDate, $endDate), $filters);
$cache[$cacheKey] = CheckfrontAPIPackagesResponse::create($this()->api(new CheckfrontAPIRequest("item", $params)));
}
return $cache[$cacheKey];
}