code: def test_batch_double_backward_gpu(self):
      x_data = cuda.to_gpu(self.x)
      y_grad = cuda.to_gpu(self.gy)
      x_grad_grad = cuda.to_gpu(self.ggx)
      gradient_check.check_double_backward(
          self.det,
          x_data,
          y_grad,
          x_grad_grad,
          **self.check_double_backward_options,
      )
  
imports: import unittest
  import numpy
  import six
  import chainer
  from chainer.backends import cuda
  from chainer import functions
  from chainer import gradient_check
  from chainer import testing
  from chainer.testing import attr
  from chainer.utils import type_check
label_desc: Use image node_id 16 for calling the DetFunctionTest obj's underlying member method code with example usage: obj.test_batch_double_backward_gpu() without return types