code: def test_pickleable(self):
      # Make sure we can pickle and unpickle the interpolant without any
      # changes in the behavior.
      seq = Halton(1, scramble=False, seed=np.random.RandomState())
  
      x = 3 * seq.random(50)
      xitp = 3 * seq.random(50)
  
      y = _1d_test_function(x)
  
      interp = self.build(x, y)
  
      yitp1 = interp(xitp)
      yitp2 = pickle.loads(pickle.dumps(interp))(xitp)
  
      assert_array_equal(yitp1, yitp2)
  
imports: import pickle
  import pytest
  import numpy
  from numpy.linalg import LinAlgError
  from numpy.testing import assert_allclose, assert_array_equal
  from scipy.stats.qmc import Halton
  from scipy.spatial import cKDTree
  from scipy.interpolate._rbfinterp import _AVAILABLE, _SCALE_INVARIANT, _NAME_TO_MIN_DEGREE, _monomial_powers, RBFInterpolator
  from scipy.interpolate import _rbfinterp_pythran
label_desc: Use image node_id 22 for calling the _TestRBFInterpolator obj's underlying member method code with example usage: obj.test_pickleable() without return types