code: func (err getError) Error() string {
  	switch err.Reason {
  	case ErrSectionNotFound:
  		return fmt.Sprintf("section '%s' not found", err.Name)
  	case ErrKeyNotFound:
  		return fmt.Sprintf("key '%s' not found", err.Name)
  	}
  	return "invalid get error"
  }
docs: // Error implements Error interface.