enumclassMyOutputs {Back,Done,}data classRetryScreen(valmessage:String,valonRetryClicked: ()->Unit,valonCancelClicked: ()->Unit,) : Screendata objectLoadingScreen :ScreenclassMyWorkflow(privatevalchild1:Workflow<Unit,String,Screen>,privatevalchild2:Workflow<Unit,String,Screen>,privatevalchild3:Workflow<String,Nothing,Screen>,privatevalnetworkCall:suspend (String)->String) : BackStackWorkflow<String, MyOutputs>() {overridesuspendfun BackStackScope.runBackStack(props:StateFlow<String>,emitOutput: (MyOutputs)->Unit  ) {// Step 1    showWorkflow(child1) { output->when (output) {"back"-> emitOutput(MyOutputs.Back)"next"-> {// Step 2val childResult= showWorkflow(child2) { output->// Removes child2 from the stack, cancels the output handler from step 1, and just// leaves child1 rendering.if (output=="back") goBack()            output          }// Step 3 – make a network call, showing a retry screen if it fails. If the user cancels// instead of retrying, we go back to showing child1.val networkResult= networkCallWithRetry(childResult)// Step 4: Show a workflow for 3 seconds then finish.          launch {            delay(3.seconds)            emitOutput(MyOutputs.Done)          }          showWorkflow(child3, flowOf(networkResult))        }else-> error("Unexpected output:$output")      }    }  }overridefuncreateIdleScreen():Screen=LoadingScreenprivatesuspendfun BackStackParentScope.networkCallWithRetry(request:String  ):String {// TODO: Show a loading screen automatically.var networkResult= networkCall(request)while (networkResult=="failure") {      showScreen {RetryScreen(          message= networkResult,          onRetryClicked= { continueWith(Unit) },// Go back to showing child1.          onCancelClicked= { goBack() }        )      }      networkResult= networkCall(request)    }return networkResult  }}