code: def check_double_backward(self, x_data, y_grad, x_grad_grad):
      gradient_check.check_double_backward(
          self.func,
          x_data,
          y_grad,
          x_grad_grad,
          dtype="d",
          **self.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
label_desc: Use image node_id 8 for calling the TrigonometricFunctionsTest obj's underlying member method code with example usage: obj.check_double_backward(x_data, y_grad, x_grad_grad) without return types