code: def __init__(
      self,
      seasonal_issms: List[SeasonalityISSM],
      add_trend: bool = DEFAULT_ADD_TREND,
  ) -> None:
      super().__init__()
      self.seasonal_issms = seasonal_issms
      self.nonseasonal_issm = (
          LevelISSM() if add_trend is False else LevelTrendISSM()
      )
  
imports: from typing import List, Sequence, Tuple
  from pandas.tseries.frequencies import to_offset
  from gluonts.core.component import validated
  from gluonts.mx import Tensor
  from gluonts.mx.distribution.distribution import getF
  from gluonts.mx.util import _broadcast_param
  from gluonts.time_feature import Constant, day_of_week_index, hour_of_day_index, minute_of_hour_index, month_of_year_index, TimeFeature, week_of_year_index, norm_freq_str
label_desc: Use image node_id 1 to create a new CompositeISSM object from inherited base classes: ISSM with example: obj = CompositeISSM(seasonal_issms, add_trend)