You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: rule.go
    path of file: ./repos/gitness/types/enum
    
    the code of the file until where you have to start completion: // Copyright 2023 Harness, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in 
    
func ParseRuleSortAttr(s string) RuleSort {
	switch strings.ToLower(s) {
	// TODO [CODE-1363]: remove after identifier migration.
	case uid:
		return RuleSortUID
	case created, createdAt:
		return RuleSortCreated
	case updated, updatedAt:
		return RuleSortUpdated
	}

	return RuleSortIdentifier
}