這是我的代碼{    saruman := map[string]int{     "power": 150,     "skills": 200,     "knowledge": 380,    }    gandalf := map[string]int{     "power": 180,     "skills": 210,     "knowledge": 240,    }    wizards := make(map[string]interface{})    wizards["saruman"] = saruman    wizards["gandalf"] = gandalf    fmt.Println(wizards)    //OK map[gandalf:map[knowledge:240 power:180 skills:210] saruman:map[knowledge:380 power:150 skills:200]]    //change gandalf property    wizards["gandalf"]["knowledge"] = 310    fmt.Println(wizards)}在最后一行，我們得到：NOK無效操作：wizards["gandalf"]["knowledge"]（類型接口{}不支持索引）