How to generate a random string of a given length in Go?

Hi everyone! I just started learning Go and came across a task: I need to generate random strings of a fixed length, for example, for creating temporary passwords or session identifiers. I tried using the `math/rand` package and simply selecting random characters from a set of letters, but I ran into a problem — the strings are not entirely random, and sometimes they even repeat. Here's my current code: ```go package main import ( "fmt" "math/rand" ) func main() { fmt.Println(randString(10)) } func randString(n int) string { var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ") b := make([]rune, n) for i := range b { b[i] = letters[rand.Intn(len(letters))] } return string(b) } ``` The problem is that