code: def main(dataset: str, group: str):
      ets = pd.read_csv(f"./data/ets-forecasts-{dataset}-{group}.csv")
      ces = pd.read_csv(f"./data/ces-forecasts-{dataset}-{group}.csv")
      df = ets.merge(ces, how="left", on=["unique_id", "ds"])
      df["ensemble"] = df[["ets", "ces"]].mean(axis=1)
      df = df[["unique_id", "ds", "ensemble"]]
      df.to_csv(
          f"./data/ensemble-forecasts-{dataset}-{group}.csv",
          index=False,
      )
  
      # time
      ets = pd.read_csv(f"./data/ets-time-{dataset}-{group}.csv")
      ces = pd.read_csv(f"./data/ces-time-{dataset}-{group}.csv")
      df = pd.DataFrame(
          {"time": ets["time"] + ces["time"], "model": "ensemble"},
          index=[0],
      )
      df.to_csv(
          f"./data/ensemble-time-{dataset}-{group}.csv", index=False
      )
  
label_desc: Use image node_id 1 for calling a global function with example usage: main(dataset, group) without return types