code: function errHandler(err) {
      process.stderr.write(chalk.red('Model generation failed!') + '\n');
  
      switch (err.code) {
        default:
          case 'PARSE_FAIL':
          if (!quiet) {
            process.stderr.write('\n' + err.stack + '\n');
          }
        break;
  
        case 'ENOENT':
            if (!quiet) {
              process.stderr.write('\n' + err.stack.replace('ENOENT, lstat ', 'unable to find ') + '\n');
            }
          break;
      }
      callback(err);
    }
docs: Handles Error object
  @param err