how to generate random data [golang] [20lines]

main.go

package main

import (
	"crypto/rand"
	"encoding/hex"
	"fmt"
)

func main() {
	src := make([]byte, 4)
	_, err := rand.Read(src)
	if err != nil {
		fmt.Println("error: ", err)
		return
	}

	fmt.Printf("random bytes: %s\n", hex.EncodeToString(src))
}