code: def test_comparemeans_convenient_interface(self):
      x1_2d, x2_2d = self.x1_2d, self.x2_2d
      d1 = DescrStatsW(x1_2d)
      d2 = DescrStatsW(x2_2d)
      cm1 = CompareMeans(d1, d2)
  
      # smoke test for summary
      from statsmodels.iolib.table import SimpleTable
  
      for use_t in [True, False]:
          for usevar in ["pooled", "unequal"]:
              smry = cm1.summary(use_t=use_t, usevar=usevar)
              assert_(isinstance(smry, SimpleTable))
  
      # test for from_data method
      cm2 = CompareMeans.from_data(x1_2d, x2_2d)
      assert_(str(cm1.summary()) == str(cm2.summary()))
  
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 6 for calling the TestWeightstats obj's underlying member method code with example usage: obj.test_comparemeans_convenient_interface() without return types