code: def test_residuez_trailing_zeros(self, xp, scp, ba):
      # Trailing zeros in numerator or denominator must not affect the
      # answer.
      ba = map(xp.asarray, ba)
      r, p, k = scp.signal.residuez(*ba)
      return r, p, k
  
imports: import numpy
  import pytest
  import cupy
  from cupy import testing
  import cupyx.scipy.signal
label_desc: Use image node_id 7 for calling the TestPartialFractionExpansion obj's underlying member method code with example usage: obj.test_residuez_trailing_zeros(xp, scp, ba) and returns: r,  p,  k