code: def test_smoketest(self):
      # Test at single points
      x = np.array(
          [(0, 0), (-0.5, -0.5), (-0.5, 0.5), (0.5, 0.5), (0.25, 0.3)],
          dtype=np.double,
      )
      y = np.arange(x.shape[0], dtype=np.double)
  
      yi = interpnd.LinearNDInterpolator(x, y)(x)
      assert_almost_equal(y, yi)
  
imports: import os
  import numpy
  from numpy.testing import assert_equal, assert_allclose, assert_almost_equal, suppress_warnings
  from pytest import raises
  import pytest
  import scipy.interpolate.interpnd
  import scipy.spatial.qhull
  import pickle
label_desc: Use image node_id 1 for calling the TestLinearNDInterpolation obj's underlying member method code with example usage: obj.test_smoketest() without return types