PendingOrders.Created

event Action<PendingOrderCreatedEventArgs> Created;

api.PendingOrders.Created += handler  # handler(obj: PendingOrderCreatedEventArgs)

protected override void OnStart()
{
    PendingOrders.Created += OnPendingOrdersCreated;
    PlaceStopOrder(TradeType.Buy, SymbolName, 10000, Symbol.Ask + 10 * Symbol.PipSize);
}

private void OnPendingOrdersCreated(PendingOrderCreatedEventArgs args)
{
    Print("Pending order with id {0} was created", args.PendingOrder.Id);
}

def on_start(self):
    api.PendingOrders.Created += self.on_pending_orders_created
    api.PlaceStopOrder(TradeType.Buy, api.SymbolName, 10000, api.Symbol.Ask + 10 * api.Symbol.PipSize)

def on_pending_orders_created(self, args):
    api.Print(f"Pending order with id {args.PendingOrder.Id} was created")