docstr: Instead of psislw data, this test uses fake data.
code: def test_ks_summary(self):
      """Instead of psislw data, this test uses fake data."""
      pareto_tail_indices = np.array(
          [0.1, 0.1, 0.1, 0.2, 0.2, 0.2, 0.2]
      )
      with pytest.warns(UserWarning):
          summary = ks_summary(pareto_tail_indices)
      assert summary is not None
      pareto_tail_indices2 = np.array(
          [0.1, 0.1, 0.1, 0.2, 0.2, 0.2, 0.6]
      )
      with pytest.warns(UserWarning):
          summary2 = ks_summary(pareto_tail_indices2)
      assert summary2 is not None
  
imports: import os
  import numpy
  import packaging
  import pandas
  import pytest
  import scipy
  from numpy.testing import assert_almost_equal
  from ...data import from_cmdstan, load_arviz_data
  from ...rcparams import rcParams
  from ...sel_utils import xarray_var_iter
  from ...stats import bfmi, ess, mcse, rhat
  from ...stats.diagnostics import _ess, _ess_quantile, _mc_error, _mcse_quantile, _multichain_statistics, _rhat, _rhat_rank, _split_chains, _z_scale, ks_summary
label_desc: Use image node_id 26 for calling the TestDiagnostics obj's underlying member method code with example usage: obj.test_ks_summary() without return types