ErrorCode

var result = ExecuteMarketOrder(TradeType.Buy, SymbolName, 10000, "myLabel", 20, 40);
if (!result.IsSuccessful)
{
    switch (result.Error)
    {
        case ErrorCode.NoMoney:
            Print("Not enough money to open the position");
            break;
        case ErrorCode.MarketClosed:
            Print("The market is closed");
            break;
        default:
            Print("Order failed: {0}", result.Error);
            break;
    }
}

result = api.ExecuteMarketOrder(TradeType.Buy, api.SymbolName, 10000, "myLabel", 20, 40)
if not result.IsSuccessful:
    if result.Error == ErrorCode.NoMoney:
        api.Print("Not enough money to open the position")
    elif result.Error == ErrorCode.MarketClosed:
        api.Print("The market is closed")
    else:
        api.Print(f"Order failed: {result.Error}")

protected override void OnError(Error error)
{
    if (error.Code == ErrorCode.BadVolume)
        Print("Bad volume");
    else if (error.Code == ErrorCode.Disconnected)
        Print("Disconnected");
    else
        Print("Error: {0}", error.Code);
}

def on_error(self, error):
    if error.Code == ErrorCode.BadVolume:
        api.Print("Bad volume")
    elif error.Code == ErrorCode.Disconnected:
        api.Print("Disconnected")
    else:
        api.Print(f"Error: {error.Code}")