code: def test_properties(self):
      # Test setters/getters for cross class properties.
      # This implicitly tests to_tf() and to_zpk()
  
      # Getters
      s = signal.StateSpace(1, 1, 1, 1, dt=0.05)
      assert s.poles == cupy.array([1])
      assert s.zeros == cupy.array([0])
  
imports: from math import sqrt, pi
  from pytest import raises
  import cupy
  from cupy import testing
  import cupyx.scipy.signal
label_desc: Use image node_id 3 for calling the TestStateSpaceDisc obj's underlying member method code with example usage: obj.test_properties() without return types