code: def test_inversion_methods(self):
      model = self.model
  
      # Clear the inversion method
      model.inversion_method = 0
  
      # Try setting via boolean
      model.invert_univariate = True
      assert_equal(model.inversion_method, INVERT_UNIVARIATE)
      model.invert_cholesky = True
      assert_equal(
          model.inversion_method, INVERT_UNIVARIATE | INVERT_CHOLESKY
      )
      model.invert_univariate = False
      assert_equal(model.inversion_method, INVERT_CHOLESKY)
  
      # Try setting directly via method
      model.set_inversion_method(INVERT_LU)
      assert_equal(model.inversion_method, INVERT_LU)
  
      # Try setting via boolean via method
      model.set_inversion_method(
          invert_cholesky=True, invert_univariate=True, invert_lu=False
      )
      assert_equal(
          model.inversion_method, INVERT_UNIVARIATE | INVERT_CHOLESKY
      )
  
      # Try setting and unsetting all
      model.inversion_method = 0
      for name in model.inversion_methods:
          setattr(model, name, True)
      assert_equal(
          model.inversion_method,
          INVERT_UNIVARIATE
          | SOLVE_LU
          | INVERT_LU
          | SOLVE_CHOLESKY
          | INVERT_CHOLESKY,
      )
      for name in model.inversion_methods:
          setattr(model, name, False)
      assert_equal(model.inversion_method, 0)
  
file_path: statsmodels/statsmodels/tsa/statespace/tests/test_options.py
imports: import numpy
  from statsmodels.tsa.statespace.kalman_filter import FILTER_CONVENTIONAL, FILTER_EXACT_INITIAL, FILTER_AUGMENTED, FILTER_SQUARE_ROOT, FILTER_UNIVARIATE, FILTER_COLLAPSED, FILTER_EXTENDED, FILTER_UNSCENTED, FILTER_CONCENTRATED, FILTER_CHANDRASEKHAR, INVERT_UNIVARIATE, SOLVE_LU, INVERT_LU, SOLVE_CHOLESKY, INVERT_CHOLESKY, STABILITY_FORCE_SYMMETRY, MEMORY_STORE_ALL, MEMORY_NO_FORECAST, MEMORY_NO_PREDICTED, MEMORY_NO_FILTERED, MEMORY_NO_LIKELIHOOD, MEMORY_NO_GAIN, MEMORY_NO_SMOOTHING, MEMORY_NO_STD_FORECAST, MEMORY_CONSERVE
  from statsmodels.tsa.statespace.kalman_smoother import SMOOTHER_STATE, SMOOTHER_STATE_COV, SMOOTHER_STATE_AUTOCOV, SMOOTHER_DISTURBANCE, SMOOTHER_DISTURBANCE_COV, SMOOTHER_ALL
  from statsmodels.tsa.statespace.simulation_smoother import SimulationSmoother, SIMULATION_STATE, SIMULATION_ALL
  from numpy.testing import assert_equal
label_desc: Use image node_id 2 for calling the TestOptions obj's underlying member method code with example usage: obj.test_inversion_methods() without return types