How to create expanding list from dictionary of Array [String: [Int]] in SwiftUI

I try to make expanding sections from dictionary of Array [String: [Int]] in SwiftUI. This Code worked but without expanding. how can i do it?

var body: some View {
    let dict : [String: [Int]] = ["key1": [1,2,3,4], "key2": [6,7,8,9]]
    Section {
        List(dict.keys.sorted(), id: \.self) { key in
             Section(header: Text(key)) {
                 ForEach(dict[key]!, id: \.self) { x in
                     Text("\(x)")
                 }
             }
        } // List
    } // Section
}

I found DisclosureGroup" in SwiftUI.

You can use the DisclosureGroup modifier to create an expandable list view in SwiftUI.

And this is how the code should be:

var body: some View {

    let dict : [String: [Int]] = ["key1": [1,2,3,4], "key2": [6,7,8,9]]
    
    Section {
        List(dict.keys.sorted(), id: \.self) { key in
            DisclosureGroup(key) {
                ForEach(dict[key]!, id: \.self) { x in
                    Text("\(x)")
                }
            }
        } // List
    } // Section
}