code: def test_find_trend_changepoints_slow(hourly_data):
      """Tests the trend changepoint detection when fast trend estimation is turned off."""
      dl = DataLoader()
      df_pt = dl.load_peyton_manning()
  
      model = ChangepointDetector()
      model.find_trend_changepoints(
          df=df_pt,
          time_col="ts",
          value_col="y",
          fast_trend_estimation=False,
      )
      assert isinstance(model.trend_model, RegressorMixin)
      assert model.trend_model.coef_.shape[0] == 100 + 1 + 8 * 2
      assert model.trend_coef.shape[0] == 100 + 1 + 8 * 2
      assert model.trend_intercept is not None
      assert model.trend_changepoints is not None
      assert model.trend_potential_changepoint_n == 100
      assert model.trend_df.shape[1] == 100 + 1 + 8 * 2
      assert model.original_df.shape == df_pt.shape
      assert model.time_col is not None
      assert model.value_col is not None
      assert model.adaptive_lasso_coef[1].shape[0] == 100 + 1 + 8 * 2
      assert model.y.index[0] not in model.trend_changepoints
  
imports: from datetime import timedelta
  import numpy
  import pandas
  import pytest
  from pandas.tseries.frequencies import to_offset
  from sklearn.base import RegressorMixin
  from testfixtures import LogCapture
  from greykite.algo.changepoint.adalasso.changepoint_detector import ChangepointDetector
  from greykite.algo.changepoint.adalasso.changepoint_detector import get_changepoints_dict
  from greykite.algo.changepoint.adalasso.changepoint_detector import get_seasonality_changepoints
  from greykite.algo.changepoint.shift_detection.shift_detector import ShiftDetection
  from greykite.common.data_loader import DataLoader
  from greykite.common.logging import LOGGER_NAME
  from greykite.common.testing_utils import generate_df_for_tests
  from greykite.common.testing_utils import generate_df_with_arbitrary_trends_and_shifts
  from greykite.common.testing_utils import generate_test_changepoint_df
label_desc: Use image node_id 4 for calling a global function with example usage: test_find_trend_changepoints_slow(hourly_data) without return types