PendingOrders.Cancelled

event Action<PendingOrderCancelledEventArgs> Cancelled;

api.PendingOrders.Cancelled += handler  # handler(obj: PendingOrderCancelledEventArgs)

protected override void OnStart()
{
    PendingOrders.Cancelled += OnPendingOrdersCancelled;
    var result = PlaceStopOrder(TradeType.Buy, SymbolName, 10000, Symbol.Ask + 10 * Symbol.PipSize);
    if (result.IsSuccessful)
        CancelPendingOrder(result.PendingOrder);
}

private void OnPendingOrdersCancelled(PendingOrderCancelledEventArgs args)
{
    Print("Pending order with id {0} was cancelled. Reason: {1}", args.PendingOrder.Id, args.Reason);
}

def on_start(self):
    api.PendingOrders.Cancelled += self.on_pending_orders_cancelled
    result = api.PlaceStopOrder(TradeType.Buy, api.SymbolName, 10000, api.Symbol.Ask + 10 * api.Symbol.PipSize)
    if result.IsSuccessful:
        api.CancelPendingOrder(result.PendingOrder)

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