code: def test_bspline_periodic_extrap(self, xp, scp):
      b = self._make_random_spline(xp, scp, n=4, k=3)
      t, c, k = b.tck
      n = t.size - (k + 1)
  
      # Direct check
      xx = xp.asarray([-1, 0, 0.5, 1])
      xy = t[k] + (xx - t[k]) % (t[n] - t[k])
      return b(xx, extrapolate="periodic"), b(xy, extrapolate=True)
  
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 12 for calling the TestBSpline obj's underlying member method code with example usage: obj.test_bspline_periodic_extrap(xp, scp) and returns: b,  b