code: def test_backward_neg_tol():
      """Check that SequentialFeatureSelector works negative tol
  
      non-regression test for #25525
      """
      X, y = make_regression(n_features=10, random_state=0)
      lr = LinearRegression()
      initial_score = lr.fit(X, y).score(X, y)
  
      sfs = SequentialFeatureSelector(
          lr,
          n_features_to_select="auto",
          direction="backward",
          tol=-1e-3,
      )
      Xr = sfs.fit_transform(X, y)
      new_score = lr.fit(Xr, y).score(Xr, y)
  
      assert 0 < sfs.get_support().sum() < X.shape[1]
      assert new_score < initial_score
  
imports: import numpy
  import pytest
  from numpy.testing import assert_array_equal
  from sklearn.cluster import KMeans
  from sklearn.datasets import make_blobs, make_classification, make_regression
  from sklearn.ensemble import HistGradientBoostingRegressor
  from sklearn.feature_selection import SequentialFeatureSelector
  from sklearn.linear_model import LinearRegression
  from sklearn.model_selection import LeaveOneGroupOut, cross_val_score
  from sklearn.neighbors import KNeighborsClassifier
  from sklearn.pipeline import make_pipeline
  from sklearn.preprocessing import StandardScaler
  from sklearn.utils.fixes import CSR_CONTAINERS
label_desc: Use image node_id 13 for calling a global function with example usage: test_backward_neg_tol() without return types