code: public static function getTransport($key, $options = [])
      {
          if (empty($key)) {
              throw new InternalServerErrorException('Missing key for SparkPost service.');
          }
  
          return new SparkPostTransport(new Client(), $key, $options);
      }
docs: @param $key
  @param $options
  
  @return \Illuminate\Mail\Transport\SparkPostTransport
  @throws \DreamFactory\Core\Exceptions\InternalServerErrorException