Golang - Add Elements to one map position

// declare the hashMap
var hashMap = make(map[int][]string)

hashMap[123] = []string{"123"}
// adding elements to the HashMap
hashMap[123] = append(hashMap[123], "abc")
hashMap[123] = append(hashMap[123], "456")

fmt.Println(hashMap)// map[123:[123 abc 456]]