code: def test_fit_in_sample_residuals_not_stored():
      """
      Test that values of in_sample_residuals are not stored after fitting
      when `store_in_sample_residuals=False`.
      """
      forecaster = ForecasterAutoreg(LinearRegression(), lags=3)
      forecaster.fit(
          y=pd.Series(np.arange(5)), store_in_sample_residuals=False
      )
      results = forecaster.in_sample_residuals
  
      assert results is None
  
file_path: skforecast/skforecast/ForecasterAutoreg/tests/test_fit.py
imports: import numpy
  import pandas
  from skforecast.ForecasterAutoreg import ForecasterAutoreg
  from sklearn.linear_model import LinearRegression
  from .fixtures_ForecasterAutoreg import y
label_desc: Use image node_id 6 for calling a global function with example usage: test_fit_in_sample_residuals_not_stored() without return types