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: hashutils.go
    path of file: ./repos/go-doudou/toolkit/hashutils
    
    the code of the file until where you have to start completion: package hashutils

import (
	"crypto/sha1"
	"encoding/base64"
	"encoding/hex"
	"fmt"
	"github.com/unionj-cloud/go-doudou/v2/toolkit/stringutils"
)

// Sha1 return 
    
func UUIDByString(input string) string {
	sum := sha1.Sum([]byte(input))
	var uuid [16]byte
	copy(uuid[:], sum[:])
	uuid[6] = (uuid[6] & 0x0f) | uint8((5&0xf)<<4)
	uuid[8] = (uuid[8] & 0x3f) | 0x80
	var buf [36]byte
	encodeHex(buf[:], uuid)
	return string(buf[:])
}