code: public function createSubscription($request)
      {
          if (!($request instanceof MWSSubscriptionsService_Model_CreateSubscriptionInput)) {
              require_once (dirname(__FILE__) . '/Model/CreateSubscriptionInput.php');
              $request = new MWSSubscriptionsService_Model_CreateSubscriptionInput($request);
          }
          $parameters = $request->toQueryParameterArray();
          $parameters['Action'] = 'CreateSubscription';
          $httpResponse = $this->_invoke($parameters);
  
          require_once (dirname(__FILE__) . '/Model/CreateSubscriptionResponse.php');
          $response = MWSSubscriptionsService_Model_CreateSubscriptionResponse::fromXML($httpResponse['ResponseBody']);
          $response->setResponseHeaderMetadata($httpResponse['ResponseHeaderMetadata']);
          return $response;
      }
docs: Create Subscription
  Create a new subscription.
  
  @param mixed $request array of parameters for MWSSubscriptionsService_Model_CreateSubscription request or MWSSubscriptionsService_Model_CreateSubscription object itself
  @see MWSSubscriptionsService_Model_CreateSubscriptionInput
  @return MWSSubscriptionsService_Model_CreateSubscriptionResponse
  
  @throws MWSSubscriptionsService_Exception