SwiftData erors in Swift Playground

Hi, I want to add a SwiftData model to my Swift Playground in Xcode 15.2, but I get errors related to iOS version, has anyone encountered this? Thanks

import Foundation
import SwiftData

struct testStruct: Identifiable {
    let id = UUID()
    var question: String
    var answer: String
}

@Model
class testClass: Identifiable {
    let id = UUID()
    var question1: testStruct
    var question2: testStruct
    var question3: testStruct
    var question4: testStruct
    var question5: testStruct
    
    init(question1: testStruct, question2: testStruct, question3: testStruct, question4: testStruct, question5: testStruct) {
        self.question1 = question1
        self.question2 = question2
        self.question3 = question3
        self.question4 = question4
        self.question5 = question5
    }
}