code: def test_branin():
      xstars = np.asarray(
          [(-np.pi, 12.275), (+np.pi, 2.275), (9.42478, 2.475)]
      )
      f_at_xstars = np.asarray([branin(xstar) for xstar in xstars])
      branin_min = np.array([0.397887] * xstars.shape[0])
      assert_array_almost_equal(f_at_xstars, branin_min)
  
file_path: scikit-optimize/skopt/tests/test_benchmarks.py
imports: import numpy
  import pytest
  from numpy.testing import assert_array_almost_equal
  from numpy.testing import assert_almost_equal
  from skopt.benchmarks import branin
  from skopt.benchmarks import hart6
label_desc: Use image node_id 1 for calling a global function with example usage: test_branin() without return types