使用动态键解组json [重复]

I'm receiving a json object that has a known-static structure inside a key that varies between 10 different values.

Consider lastname can be any in a list of 10 lastnames:

var lastnames = [...]string { "Smith", "Johnson", "Williams", "Brown", "Jones", "Miller", "Davis", "Garcia", "Rodriguez", "Wilson" }

Now, this is how the json looks:

{ 
  (lastname here): 
    {
        "position": value,
        "user_email": value
    }
}

I tried to unmarshall it using the following structs, but i only get null values:

type Inside struct {
    Rol   string   `json:"position"`
    Email   string   `json:"user_email"`
}

type Outside struct {
    Key Inside
}

...
var outside Outside
json.Unmarshal([]byte(body), &outside)

Is it possible to unmarshall this directly without creating 10 different structs? Is there possible workaround?

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