// slice
	sl := []string{}
	fmt.Println("slice is", sl)

	sl2 := append(sl, "bb")
	fmt.Println(fmt.Printf("sl2: %s, Len: %d, Cap: %d", sl2, len(sl2), cap(sl2)))
	sl3 := append(sl2, "cc")
	fmt.Println(fmt.Printf("sl3: %s, Len: %d, Cap: %d", sl3, len(sl3), cap(sl3)))

	for key, val := range sl3 {
		fmt.Printf("%d: %s\n", key, val)
	}

slice is []
sl2: [bb], Len: 1, Cap: 125 <nil>
sl3: [bb cc], Len: 2, Cap: 228 <nil>
0: bb
1: cc