code: def check_double_backward(
      self, x_data, y_grad, x_grad_grad, use_cudnn="always"
  ):
      def f(x):
          y = F.upsampling_2d(
              x,
              self.indices,
              ksize=self.ksize,
              stride=self.stride,
              outsize=self.in_shape[2:],
          )
          return y * y
  
      with chainer.using_config("use_cudnn", use_cudnn):
          gradient_check.check_double_backward(
              f,
              x_data,
              y_grad,
              x_grad_grad,
              dtype="d",
              **self.check_double_backward_options,
          )
  
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  import chainer.functions
  from chainer import gradient_check
  from chainer import testing
  from chainer.testing import attr
  from chainer.utils import conv
label_desc: Use image node_id 8 for calling the TestUpsampling2D obj's underlying member method code with example usage: obj.check_double_backward(x_data, y_grad, x_grad_grad, use_cudnn) and returns: unknown