content: from neuralforecast.common.enums import TimeSeriesDatasetEnum
  from neuralforecast.utils import AirPassengersPanel, AirPassengersStatic
  from neuralforecast.utils import augment_calendar_df
  
  def air_passengers(h=12, augment_calendar=False, simple_augment=True):
      panel = AirPassengersPanel.copy()
      calendar_cols = None
      if augment_calendar:
          if simple_augment:
              calendar_col = 'quarter'
              panel[calendar_col] = panel[TimeSeriesDatasetEnum.Datetime].dt.quarter
              calendar_cols = [calendar_col]
          else:
              panel, calendar_cols = augment_calendar_df(df=panel, freq='M')
  
      Y_train_df = panel[panel.ds<panel[TimeSeriesDatasetEnum.Datetime].values[-h]] # 132 train
      Y_test_df = panel[panel.ds>=panel[TimeSeriesDatasetEnum.Datetime].values[-h]].reset_index(drop=True) # 12 test    
      return Y_train_df, Y_test_df, calendar_cols, AirPassengersStatic
  