code: def get_descriptives(cls, ddof=0):
      cls.descriptive = DescrStatsW(cls.data, cls.weights, ddof)
  
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 1 for calling the CheckExternalMixin obj's underlying member method code with example usage: obj.get_descriptives(cls, ddof) without return types