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: stringutils.go
    path of file: ./repos/podman/vendor/github.com/containers/storage/pkg/stringutils
    
    the code of the file until where you have to start completion: // Package stringutils provides helper functions for dealing with strings.
package stringutils

import (
	"bytes"
	"math/rand"
	"strings"
)

// GenerateRandomAlphaOnlyString gene
    
func GenerateRandomAlphaOnlyString(n int) string {
	// make a really long string
	letters := []byte("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
	b := make([]byte, n)
	for i := range b {
		b[i] = letters[rand.Intn(len(letters))]
	}
	return string(b)
}