code: private function convertUpdateReportAcknowledgements($request)
      {
  
          $parameters = array();
          $parameters['Action'] = 'UpdateReportAcknowledgements';
          if ($request->isSetMarketplace()) {
              $parameters['Marketplace'] = $request->getMarketplace();
          }
          if ($request->isSetMerchant()) {
              $parameters['Merchant'] = $request->getMerchant();
          }
          if ($request->isSetReportIdList()) {
              $reportIdList = $request->getReportIdList();
              foreach ($reportIdList->getId() as $idIndex => $id) {
                  $parameters['ReportIdList' . '.' . 'Id' . '.' . ($idIndex + 1)] = $id;
              }
          }
          if ($request->isSetAcknowledged()) {
              $parameters['Acknowledged'] = $request->getAcknowledged() ? "true" : "false";
          }
          if ($request->isSetMWSAuthToken()) {
              $parameters['MWSAuthToken'] = $request->getMWSAuthToken();
          }
  
          return array(CONVERTED_PARAMETERS_KEY => $parameters, CONVERTED_HEADERS_KEY => $this->defaultHeaders);
      }
docs: Convert UpdateReportAcknowledgementsRequest to name value pairs
  @param MarketplaceWebService_Model_UpdateReportAcknowledgementsRequest $request
  @return array