code: def test_rbf_sampler_gamma_scale():
      """Check the inner value computed when `gamma='scale'`."""
      X, y = [[0.0], [1.0]], [0, 1]
      rbf = RBFSampler(gamma="scale")
      rbf.fit(X, y)
      assert rbf._gamma == pytest.approx(4)
  
imports: import re
  import numpy
  import pytest
  from sklearn.datasets import make_classification
  from sklearn.kernel_approximation import AdditiveChi2Sampler, Nystroem, PolynomialCountSketch, RBFSampler, SkewedChi2Sampler
  from sklearn.metrics.pairwise import chi2_kernel, kernel_metrics, polynomial_kernel, rbf_kernel
  from sklearn.utils._testing import assert_allclose, assert_array_almost_equal, assert_array_equal
  from sklearn.utils.fixes import CSR_CONTAINERS
label_desc: Use image node_id 13 for calling a global function with example usage: test_rbf_sampler_gamma_scale() without return types