code: def check_forward(self, h_data, x_data):
      h = chainer.Variable(h_data)
      x = chainer.Variable(x_data)
      y = self._forward(self.link, h, x)
  
      self.assertEqual(y.data.dtype, numpy.float32)
      y_expect = _gru(self.link, h_data, x_data)
      testing.assert_allclose(y_expect, y.data)
      if isinstance(self.link, links.StatefulGRU):
          testing.assert_allclose(self.link.h.data, y.data)
  
imports: import unittest
  import numpy
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import gradient_check
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 3 for calling the TestGRU obj's underlying member method code with example usage: obj.check_forward(h_data, x_data) without return types