code: def setup_class(cls):
      cls.dist_equivalents = [
          # transf, stats.lognorm(1))
          # The below fails on the SPARC box with scipy 10.1
          # (lognormalg, stats.lognorm(1)),
          # transf2
          (squarenormalg, stats.chi2(1)),
          (absnormalg, stats.halfnorm),
          (absnormalg, stats.foldnorm(1e-5)),  # try frozen
          # (negsquarenormalg, 1-stats.chi2),  # will not work as distribution
          (squaretg(10), stats.f(1, 10)),
      ]  # try both frozen
  
      l, s = 0.0, 1.0
      cls.ppfq = [0.1, 0.5, 0.9]
      cls.xx = [0.95, 1.0, 1.1]
      cls.nxx = [-0.95, -1.0, -1.1]
  
file_path: statsmodels/statsmodels/sandbox/distributions/tests/test_transf.py
imports: import warnings
  import numpy
  from numpy.testing import assert_almost_equal
  from scipy import stats, special
  from statsmodels.sandbox.distributions.extras import squarenormalg, absnormalg, negsquarenormalg, squaretg
label_desc: Use image node_id 1 for calling the Test_Transf2 obj's underlying member method code with example usage: obj.setup_class(cls) without return types