code: def test_dlsim_6(self, xp, scp):
      # zeros-poles-gain representation
      zd = xp.array([0.5, -0.5])
      pd = xp.array([1.0j / sqrt(2), -1.0j / sqrt(2)])
      k = 1.0
  
      u = xp.hstack(
          (
              xp.linspace(0, 4.0, num=5)[:, None],
              xp.full((5, 1), 0.01),
              xp.full((5, 1), -0.002),
          )
      )
      t_in = xp.linspace(0, 2.0, num=5)
  
      tout, yout = scp.signal.dlsim((zd, pd, k, 0.5), u[:, 0], t_in)
      return tout, yout
  
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 6 for calling the TestDLTI obj's underlying member method code with example usage: obj.test_dlsim_6(xp, scp) and returns: tout,  yout