code: func OpenFile(path string) (*os.File, error) {
  	newPath, err := NormalizePath(path)
  	if err != nil {
  		return nil, trace.Wrap(err)
  	}
  	fi, err := os.Stat(newPath)
  	if err != nil {
  		return nil, trace.ConvertSystemError(err)
  	}
  	if fi.IsDir() {
  		return nil, trace.BadParameter("%v is not a file", path)
  	}
  	f, err := os.Open(newPath)
  	if err != nil {
  		return nil, trace.ConvertSystemError(err)
  	}
  	return f, nil
  }
docs: // OpenFile opens  file and returns file handle