package main

import (
	"crypto/hmac"
	"crypto/sha1"
	"encoding/base64"
	"fmt"
)

func main() {
	key := []byte("aaaaaa")
	mac := hmac.New(sha1.New, key)
	mac.Write([]byte("Hello World!"))
	hmacSum := mac.Sum(nil)

	fmt.Printf("%x\n", hmacSum)
	fmt.Printf("%s\n", base64.StdEncoding.EncodeToString(hmacSum))
}