code: def test_forecast_simple_silverkite_seasonality_changepoints():
      dl = DataLoader()
      df = dl.load_peyton_manning()
      no_change_prop = 0.3
      silverkite = SimpleSilverkiteForecast()
      trained_model = silverkite.forecast_simple(
          df=df,
          time_col="ts",
          value_col="y",
          changepoints_dict={
              "method": "auto",
              "no_changepoint_proportion_from_end": no_change_prop,
          },
          seasonality_changepoints_dict={
              "no_changepoint_proportion_from_end": no_change_prop,
              "regularization_strength": 0.4,
          },
      )
      changepoints = trained_model["seasonality_changepoint_dates"]
      df_length = df.shape[0]
      # has change points
      assert max([len(value) for value in changepoints.values()]) > 0
      # checks no change points at the end
      assert max(
          [max(value) for value in changepoints.values()]
      ) <= pd.to_datetime(
          df["ts"].iloc[int(df_length * (1 - no_change_prop))]
      )
  
imports: import datetime
  import math
  import sys
  import warnings
  from datetime import timedelta
  import pandas
  import pytest
  from testfixtures import LogCapture
  import greykite.common.constants
  from greykite.algo.changepoint.adalasso.changepoint_detector import ChangepointDetector
  from greykite.algo.forecast.silverkite.constants.silverkite_column import SilverkiteColumn
  from greykite.algo.forecast.silverkite.constants.silverkite_holiday import SilverkiteHoliday
  from greykite.algo.forecast.silverkite.constants.silverkite_seasonality import SilverkiteSeasonality
  from greykite.algo.forecast.silverkite.constants.silverkite_seasonality import SilverkiteSeasonalityEnum
  from greykite.algo.forecast.silverkite.forecast_simple_silverkite import SimpleSilverkiteForecast
  from greykite.algo.forecast.silverkite.forecast_simple_silverkite_helper import generate_holiday_events
  from greykite.common.constants import CHANGEPOINT_COL_PREFIX
  from greykite.common.constants import EVENT_DF_DATE_COL
  from greykite.common.constants import EVENT_DF_LABEL_COL
  from greykite.common.constants import LOGGER_NAME
  from greykite.common.constants import TIME_COL
  from greykite.common.constants import VALUE_COL
  from greykite.common.data_loader import DataLoader
  from greykite.common.enums import SimpleTimeFrequencyEnum
  from greykite.common.enums import TimeEnum
  from greykite.common.features.timeseries_features import get_available_holidays_across_countries
  from greykite.common.features.timeseries_features import get_holidays
  from greykite.common.python_utils import assert_equal
  from greykite.common.python_utils import update_dictionary
  from greykite.common.testing_utils import generate_df_for_tests
  from greykite.common.testing_utils import generate_df_with_reg_for_tests
label_desc: Use image node_id 12 for calling a global function with example usage: test_forecast_simple_silverkite_seasonality_changepoints() without return types