code: def test_holiday_grouper_init(daily_df, holiday_df):
      """Tests the initialization of `HolidayGrouper`."""
      # Tests pre-processing.
      hg = HolidayGrouper(
          df=daily_df,
          time_col=TIME_COL,
          value_col=VALUE_COL,
          holiday_df=holiday_df,
          holiday_date_col=EVENT_DF_DATE_COL,
          holiday_name_col=EVENT_DF_LABEL_COL,
          holiday_impact_pre_num_days=0,
          holiday_impact_post_num_days=0,
          holiday_impact_dict=None,
          get_suffix_func=None,
      )
      # After initialization, a new column (is not already exists)
      # will be added to `holiday_df` and `expanded_holiday_df`.
      assert HOLIDAY_NAME_COL in hg.holiday_df.columns
      assert HOLIDAY_NAME_COL in hg.expanded_holiday_df.columns
  
file_path: greykite/greykite/tests/algo/common/test_holiday_grouper.py
imports: import pandas
  import pytest
  from greykite.algo.common.holiday_grouper import HolidayGrouper
  from greykite.algo.common.holiday_utils import HOLIDAY_NAME_COL
  from greykite.algo.common.holiday_utils import get_weekday_weekend_suffix
  from greykite.common.constants import EVENT_DF_DATE_COL
  from greykite.common.constants import EVENT_DF_LABEL_COL
  from greykite.common.constants import TIME_COL
  from greykite.common.constants import VALUE_COL
  from greykite.common.data_loader import DataLoader
  from greykite.common.features.timeseries_features import get_holidays
  from greykite.common.python_utils import assert_equal
label_desc: Use image node_id 4 for calling a global function with example usage: test_holiday_grouper_init(daily_df, holiday_df) without return types