code: public function getFulfillmentOrder($request)
      {
          if (!($request instanceof FBAOutboundServiceMWS_Model_GetFulfillmentOrderRequest)) {
              $request = new FBAOutboundServiceMWS_Model_GetFulfillmentOrderRequest($request);
          }
          $parameters = $request->toQueryParameterArray();
          $parameters['Action'] = 'GetFulfillmentOrder';
          $httpResponse = $this->_invoke($parameters);
  
          $response = FBAOutboundServiceMWS_Model_GetFulfillmentOrderResponse::fromXML($httpResponse['ResponseBody']);
          $response->setResponseHeaderMetadata($httpResponse['ResponseHeaderMetadata']);
          return $response;
      }
docs: Get Fulfillment Order
  Get detailed information about a FulfillmentOrder.  This includes the
  original fulfillment order request, the status of the order and its
  items in Amazon's fulfillment network, and the shipments that have been
  generated to fulfill the order.
  
  @param mixed $request array of parameters for FBAOutboundServiceMWS_Model_GetFulfillmentOrder request or FBAOutboundServiceMWS_Model_GetFulfillmentOrder object itself
  @see FBAOutboundServiceMWS_Model_GetFulfillmentOrderRequest
  @return FBAOutboundServiceMWS_Model_GetFulfillmentOrderResponse
  
  @throws FBAOutboundServiceMWS_Exception