public function update(CustomCollection &$customCollection)
    {
        $data = $customCollection->exportData();
        $endpoint = '/admin/custom_collections/'.$customCollection->id.'.json';
        $response = $this->request(
            $endpoint, 'PUT', array(
            'custom_collection' => $data
            )
        );
        $customCollection->setData($response['custom_collection']);
    }