code: def test_output_get_feature_importances_when_regressor_is_RandomForest():
      """
      Test output of get_feature_importances when regressor is RandomForestRegressor with lags=3
      and it is trained with y=pd.Series(np.arange(10)).
      """
      forecaster = ForecasterAutoreg(
          RandomForestRegressor(
              n_estimators=1, max_depth=2, random_state=123
          ),
          lags=3,
      )
      forecaster.fit(y=pd.Series(np.arange(10)))
  
      results = forecaster.get_feature_importances()
      expected = pd.DataFrame(
          {
              "feature": ["lag_1", "lag_2", "lag_3"],
              "importance": np.array([0.94766355, 0.0, 0.05233645]),
          }
      ).sort_values(by="importance", ascending=False)
  
      pd.testing.assert_frame_equal(results, expected)
  
file_path: skforecast/skforecast/ForecasterAutoreg/tests/test_get_feature_importances.py
imports: import re
  import pytest
  from pytest import approx
  import numpy
  import pandas
  from skforecast.ForecasterAutoreg import ForecasterAutoreg
  from sklearn.exceptions import NotFittedError
  from sklearn.pipeline import make_pipeline
  from sklearn.preprocessing import StandardScaler
  from sklearn.linear_model import LinearRegression
  from sklearn.neural_network import MLPRegressor
  from sklearn.ensemble import RandomForestRegressor
label_desc: Use image node_id 2 for calling a global function with example usage: test_output_get_feature_importances_when_regressor_is_RandomForest() without return types