code: func OutputVersion(cmd *cobra.Command, defaultVersion *unversioned.GroupVersion) (unversioned.GroupVersion, error) {
  	outputVersionString := GetFlagString(cmd, "output-version")
  	if len(outputVersionString) == 0 {
  		if defaultVersion == nil {
  			return unversioned.GroupVersion{}, nil
  		}
  
  		return *defaultVersion, nil
  	}
  
  	return unversioned.ParseGroupVersion(outputVersionString)
  }
docs: // OutputVersion returns the preferred output version for generic content (JSON, YAML, or templates)
  // defaultVersion is never mutated.  Nil simply allows clean passing in common usage from client.Config