code: def test_invalid_groups(self):
      self.link = links.GroupNormalization(groups=3)
      with self.assertRaises(ValueError):
          self.link(self.x)
  
imports: import unittest
  import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import links
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 2 for calling the TestInvalidInitialize obj's underlying member method code with example usage: obj.test_invalid_groups() without return types