code: def test_cases(self):
      for case in self.cases:
          self.check_continuous_case(case[0], case[1])
          self.check_discrete_case(case[0], case[1])
          self.check_discrete_case(case[0], case[1], method="direct")
          self.check_discrete_case(case[0], case[1], method="bilinear")
  
imports: import os
  import numpy
  from numpy.testing import assert_array_almost_equal, assert_allclose
  import pytest
  from pytest import raises
  from scipy.linalg import solve_sylvester
  from scipy.linalg import solve_continuous_lyapunov, solve_discrete_lyapunov
  from scipy.linalg import solve_continuous_are, solve_discrete_are
  from scipy.linalg import block_diag, solve, LinAlgError
  from scipy.sparse._sputils import matrix
label_desc: Use image node_id 4 for calling the TestSolveLyapunov obj's underlying member method code with example usage: obj.test_cases() without return types