code: def check_forward(self, x_data, t_data):
      x = chainer.Variable(x_data)
      t = chainer.Variable(t_data)
      y = functions.select_item(x, t)
      y_exp = cuda.to_cpu(x_data)[
          range(t_data.size), cuda.to_cpu(t_data)
      ]
  
      self.assertEqual(y.data.dtype, self.dtype)
      numpy.testing.assert_equal(cuda.to_cpu(y.data), y_exp)
  
imports: import unittest
  import numpy
  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
label_desc: Use image node_id 2 for calling the TestSelectItem obj's underlying member method code with example usage: obj.check_forward(x_data, t_data) without return types