code: def test_multi_series_dataset(self):
      # processing _to_multi_series takes a long time. Test function with 5 cols.
      ts = ele_multi_series_dataset.load().pd_dataframe()
  
      ms = ElectricityDataset()._to_multi_series(ts)
      assert len(ms) == 5
      assert len(ms[0]) == 105216
  
      multi_series_datasets = [
          UberTLCDataset,
          ILINetDataset,
          ExchangeRateDataset,
          TrafficDataset,
          WeatherDataset,
      ]
      for dataset in multi_series_datasets:
          ms = dataset()._to_multi_series(ts)
          assert len(ms) == 5
          assert len(ms[0]) == len(ts.index)
  
file_path: darts/darts/tests/datasets/test_dataset_loaders.py
imports: import os
  import shutil
  import tempfile
  import pytest
  from darts import TimeSeries
  from darts.datasets import _DEFAULT_PATH, AirPassengersDataset, AusBeerDataset, AustralianTourismDataset, ElectricityConsumptionZurichDataset, ElectricityDataset, EnergyDataset, ETTh1Dataset, ETTh2Dataset, ETTm1Dataset, ETTm2Dataset, ExchangeRateDataset, GasRateCO2Dataset, HeartRateDataset, IceCreamHeaterDataset, ILINetDataset, MonthlyMilkDataset, MonthlyMilkIncompleteDataset, SunspotsDataset, TaylorDataset, TemperatureDataset, TrafficDataset, UberTLCDataset, USGasolineDataset, WeatherDataset, WineDataset, WoolyDataset
  from darts.datasets.dataset_loaders import DatasetLoader, DatasetLoaderCSV, DatasetLoaderMetadata, DatasetLoadingException
label_desc: Use image node_id 6 for calling the TestDatasetLoader obj's underlying member method code with example usage: obj.test_multi_series_dataset() without return types