code: def setup_class(cls):
      true = {
          "params": np.r_[
              0.754673,
              0.095915,
              -0.358811,
              1.163516,
              np.exp(-0.262658) ** 2,
              0.013486,
              -0.057521,
          ],
          "llf": -10.14066,
          "llf_fit": -4.0523073,
          "llf_fit_em": -8.885836,
      }
      super().setup_class(
          true, rgnp[-10:], k_regimes=2, order=2, switching_ar=False
      )
  
imports: import warnings
  import os
  import numpy
  from numpy.testing import assert_equal, assert_allclose
  import pandas
  import pytest
  from statsmodels.tools import add_constant
  from statsmodels.tsa.regime_switching import markov_autoregression
label_desc: Use image node_id 1 for calling the TestHamiltonAR2Short obj's underlying member method code with example usage: obj.setup_class(cls) without return types