code: def test_confint_mean(self):
      # compare confint_mean with ttest
      d1w = self.d1w
      alpha = 0.05
      low, upp = d1w.tconfint_mean()
      t, p, d = d1w.ttest_mean(low)
      assert_almost_equal(p, alpha * np.ones(p.shape), 8)
      t, p, d = d1w.ttest_mean(upp)
      assert_almost_equal(p, alpha * np.ones(p.shape), 8)
      t, p, d = d1w.ttest_mean(np.vstack((low, upp)))
      assert_almost_equal(p, alpha * np.ones(p.shape), 8)
  
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 4 for calling the CheckWeightstats1dMixin obj's underlying member method code with example usage: obj.test_confint_mean() without return types