IndicatorDataSeries

public partial class MedianPriceSma : Indicator
{
    private IndicatorDataSeries _medianPrices;
    private SimpleMovingAverage _sma;

    protected override void Initialize()
    {
        // A data series that is not an output in config.json must be created with CreateDataSeries
        _medianPrices = CreateDataSeries();
        _sma = Indicators.SimpleMovingAverage(_medianPrices, 14);
    }

    public override void Calculate(int index)
    {
        _medianPrices[index] = (Bars.HighPrices[index] + Bars.LowPrices[index]) / 2;
        Result[index] = _sma.Result[index];
    }
}

import clr
clr.AddReference("cAlgo.API")

from cAlgo.API import *

class MedianPriceSma():
    def initialize(self):
        self.medianPrices = api.CreateDataSeries()
        self.sma = api.Indicators.SimpleMovingAverage(self.medianPrices, 14)

    def calculate(self, index):
        self.medianPrices[index] = (api.Bars.HighPrices[index] + api.Bars.LowPrices[index]) / 2
        api.Result[index] = self.sma.Result[index]

{
  "AccessRights": "None",
  "IsOverlay": false,
  "LineOutputs": [
    {
      "Name": "Result",
      "DisplayName": "Main",
      "Color": "Orange"
    }
  ]
}