code: func Set(key, value string) error {
  	err := _Set(_SETTINGS.user, key, value)
  	if err != nil {
  		return err
  	}
  
  	if _SETTINGS.useKDE {
  		return _Set(_SETTINGS.kde, key, value)
  	}
  	return nil
  }
docs: // == Set session-wide variables
  // Set sets the value of the environment variable named by the key that
  // affects the current user.
  // It returns an error, if any.