UserDefaults 객체 제거

UserDefaults.standard.removeObject(forKey: "helloWorldStringKey")

 for (key, value) in UserDefaults.standard.dictionaryRepresentation() {
   print("\(key) = \(value) \n")
 }

_=UserDefaults.standard.dictionaryRepresentation().map {print("[UserDefaults_CleandUp]:\($0.key): \($0.value)")}

UserDefaults.standard.dictionaryRepresentation().forEach{ print("[UserDefaults_CleandUp]:\($0.key): \($0.value)") }