code: def test_xi_1d(self):
      # verify that 1-D xi works as expected
      points, values = self._sample_4d_data()
      sample = cp.asarray([0.1, 0.1, 10.0, 9.0])
      v1 = interpn(points, values, sample, bounds_error=False)
      v2 = interpn(points, values, sample[None, :], bounds_error=False)
      assert_allclose(v1, v2)
  
imports: import pytest
  import cupy
  from cupy.testing import assert_allclose, assert_array_equal, assert_array_almost_equal
  from cupy_backends.cuda.api import runtime
  from pytest import raises
  from cupyx.scipy.interpolate import RegularGridInterpolator, interpn
label_desc: Use image node_id 7 for calling the TestInterpN obj's underlying member method code with example usage: obj.test_xi_1d() without return types