code: private function generateSetters(array $colSchema, string $tplDir): string
      {
          $setterName = sprintf('set%s', ucfirst($colSchema['mappingName']));
  
          $config = [
              'tplFilename' => 'setter',
              'tplDir'      => $tplDir,
          ];
  
          $data = [
              'type'       => $colSchema['phpType'],
              'methodName' => $setterName,
              'paramName'  => $colSchema['mappingVar'],
              'property'   => $colSchema['mappingName'],
          ];
  
          $gen = new FileGenerator($config);
  
          return $gen->render($data);
      }
docs: @param array  $colSchema
  @param string $tplDir
  
  @return string