code: def min_train_series_length(self) -> int:
      if (
          self.season_mode != SeasonalityMode.NONE
          and self.seasonality_period
          and self.seasonality_period > 1
      ):
          return 2 * self.seasonality_period
      else:
          return 3
  
imports: import math
  from typing import List, Optional
  import numpy
  import statsmodels.tsa.holtwinters
  from darts.logging import get_logger, raise_if_not, raise_log
  from darts.models.forecasting.forecasting_model import LocalForecastingModel
  from darts.timeseries import TimeSeries
  from darts.utils.statistics import check_seasonality, extract_trend_and_seasonality, remove_from_series
  from darts.utils.utils import ModelMode, SeasonalityMode, TrendMode
label_desc: Use image node_id 5 for calling the Theta obj's underlying member method code with example usage: obj.min_train_series_length() and returns: unknown, int