anchor.diff:      print('Dart DevTools version ${await _getVersion()}');
       print('');
       _printUsage(verbose);
  +    return null;
  +  }
  +
  +  if (version) {
  +    final versionStr = await _getVersion();
  +    printOutput(
  +      'Dart DevTools version $versionStr',
  +      {
  +        'version': versionStr,
  +      },
  +      machineMode: machineMode,
  +    );
       return null;
     }
   
  
positive.code: 
    parser
      ..addFlag(
        argVerbose,
        negatable: false,
        abbr: 'v',
  
negative.code: const argProfileMemory = 'record-memory-profile';
  const argTryPorts = 'try-ports';
  const argVerbose = 'verbose';
  const argVersion = 'version';
  const launchDevToolsService = 'launchDevTools';
  
  const defaultTryPorts = 10;
  