code: def test_get_data_inventory():
      dl = DataLoader()
      file_names = dl.get_data_inventory()
      assert set(file_names) == {
          "online_retail",
          "minute_energy_appliance",
          "minute_household_power",
          "minute_yosemite_temps",
          "hourly_parking",
          "hourly_traffic_volume",
          "hourly_bikesharing",
          "hourly_beijing_pm",
          "hourly_solarpower",
          "hourly_windpower",
          "hourly_electricity",
          "hourly_sf_traffic",
          "daily_temperature_australia",
          "daily_demand_order",
          "daily_female_births",
          "daily_hierarchical_actuals",
          "daily_hierarchical_forecasts",
          "daily_istanbul_stock",
          "daily_peyton_manning",
          "daily_bitcoin_transactions",
          "monthly_shampoo",
          "monthly_sunspot",
          "monthly_sunspot_monash",
          "monthly_fred_housing",
      }
  
imports: import os
  import re
  import pandas
  import pytest
  from greykite.common.constants import TIME_COL
  from greykite.common.data_loader import DataLoader
  from greykite.common.testing_utils import assert_equal
label_desc: Use image node_id 5 for calling a global function with example usage: test_get_data_inventory() without return types