code: def test_mvsk(self):
      mvsk = stats.describe(self.rvs)[-4:]
      assert_allclose(self.dist2.mvsk, mvsk, rtol=1e-12)
  
file_path: statsmodels/statsmodels/sandbox/distributions/tests/test_norm_expan.py
imports: import pytest
  import numpy
  from scipy import stats
  from numpy.testing import assert_allclose, assert_array_less
  from statsmodels.sandbox.distributions.extras import NormExpan_gen
label_desc: Use image node_id 3 for calling the TestExpandNormSample obj's underlying member method code with example usage: obj.test_mvsk() without return types