code: def test_var(self):
      # Use vardef=wgt option in SAS to match
      var = self.descriptive.var
      assert_allclose(var, self.var, rtol=1e-4)
  
imports: import numpy
  from scipy import stats
  import pandas
  from numpy.testing import assert_, assert_almost_equal, assert_allclose
  from statsmodels.stats.weightstats import DescrStatsW, CompareMeans, ttest_ind, ztest, zconfint
  from statsmodels.tools.testing import Holder
label_desc: Use image node_id 5 for calling the CheckExternalMixin obj's underlying member method code with example usage: obj.test_var() without return types