Custom columns on BackendlessUser model - direct access to fields

I came up with the following for easy retrieval/setting of custom properties/columns, although I’m not sure if there’s a better way:

extension BackendlessUser {
    var testColumn: String {
        get {
            self.properties["testColumn"] as! String
        }
        set {
            self.properties["testColumn"] = newValue
        }
    }
    //... add other columns as needed
}