преобразование ответного файла mashape api в строку php

Ниже приведен мой код, я пытаюсь получить конкретный ответ API-интерфейса mashape в строке php.

require_once 'vendor/autoload.php';
$response = Unirest\Request::get("https://sphirelabs-mobile-number-portability-india-operator-v1.p.mashape.com/index.php?number=8055144322",
array(
"X-Mashape-Key" => "XXXXXXXXX",
"Accept" => "application/json")
);
json_decode($response, true);
echo $response['operator'];

Отклик:

Unirest\Response Object (
[code] => 200
[raw_body] => {"Telecom circle":"Maharashtra","Operator":"Reliance GSM","Is MNP":"False"}
[body] => stdClass Object (
[Telecom circle] => Maharashtra
[Operator] => Reliance GSM
[Is MNP] => False
)
[headers] => Array ( [0] => HTTP/1.1 200 OK [Accept-Ranges] => none [Content-Encoding] => gzip [Content-Type] => application/json [Date] => Thu, 19 Feb 2015 14:04:39 GMT [Server] => Mashape/5.0.6 [Vary] => Accept-Encoding [Content-Length] => 91 [Connection] => keep-alive ) )