code: def test_smoothconf_data(self):
      kern = self.kern
      crit = 1.9599639845400545  # norm.isf(0.05 / 2)
      # no reference results saved to csv yet
      fitted_x = np.array([kern.smoothconf(x, y, xi) for xi in x])
  
imports: import os
  import numpy
  from numpy.testing import assert_allclose, assert_array_less
  import pandas
  import pytest
  from statsmodels.sandbox.nonparametric import kernels
label_desc: Use image node_id 2 for calling the CheckKernelMixin obj's underlying member method code with example usage: obj.test_smoothconf_data() without return types