code: def test_cmplx(self, xp, scp):
      b = self._make_random_spline(xp, scp)
      t, c, k = b.tck
      cc = c * (1.0 + 3.0j)
  
      b = scp.interpolate.BSpline(t, cc, k)
      b_re = scp.interpolate.BSpline(t, b.c.real, k)
      b_im = scp.interpolate.BSpline(t, b.c.imag, k)
  
      xx = xp.linspace(t[k], t[-k - 1], 20)
      return b(xx), b_re(xx) + 1j * b_im(xx)
  
imports: import pytest
  import inspect
  from cupy import testing
  from cupy_backends.cuda.api import driver
  from cupy_backends.cuda.api import runtime
  import numpy
  import cupyx.scipy.interpolate
label_desc: Use image node_id 18 for calling the TestBSpline obj's underlying member method code with example usage: obj.test_cmplx(xp, scp) and returns: b,  unknown