code: func NewFSLocalKeyStore(dirPath string) (s *FSLocalKeyStore, err error) {
  	dirPath, err = initKeysDir(dirPath)
  	if err != nil {
  		return nil, trace.Wrap(err)
  	}
  
  	return &FSLocalKeyStore{
  		log: logrus.WithFields(logrus.Fields{
  			trace.Component: teleport.ComponentKeyStore,
  		}),
  		KeyDir: dirPath,
  	}, nil
  }
docs: // NewFSLocalKeyStore creates a new filesystem-based local keystore object
  // and initializes it.
  //
  // If dirPath is empty, sets it to ~/.tsh.