code: def check_forward_invalid_none(self, *inputs_data):
      inputs_variable = [
          chainer.Variable(v) if v is not None else v
          for v in inputs_data
      ]
      self.assertRaises(ValueError, self.link, *inputs_variable)
  
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
  from chainer.testing import condition
label_desc: Use image node_id 11 for calling the TestTreeLSTM obj's underlying member method code with example usage: obj.check_forward_invalid_none() without return types