code: def dedup_holiday_dict(holidays_dict):
      """Removes duplicates from get_holidays output
  
      :param holidays_dict: dict(str, pd.DataFrame(EVENT_DF_DATE_COL, EVENT_DF_LABEL_COL))
          dictionary from get_holidays
      :return:
          concatenates rows of all DataFrames in holiday_df
          drops duplicate holiday names
      """
      result = pd.DataFrame()
      for country, country_holiday_df in holidays_dict.items():
          result = pd.concat([result, country_holiday_df], axis=0)
      result.drop_duplicates(inplace=True)
      return result
  
file_path: greykite/greykite/algo/forecast/silverkite/forecast_simple_silverkite_helper.py
imports: import warnings
  import pandas
  from greykite.common import constants
  from greykite.common.constants import EVENT_DF_DATE_COL
  from greykite.common.constants import EVENT_DF_LABEL_COL
  from greykite.common.constants import EVENT_INDICATOR
  from greykite.common.features.timeseries_features import add_event_window_multi
  from greykite.common.features.timeseries_features import get_fourier_col_name
  from greykite.common.features.timeseries_features import get_holidays
  from greykite.common.python_utils import split_offset_str
label_desc: Use image node_id 2 for calling a global function with example usage: dedup_holiday_dict(holidays_dict) and returns: result