code: def test_small_cpu(self):
      self._test_small(gpu=-1)
  
file_path: chainerrl/tests/links_tests/test_empirical_normalization.py
imports: import unittest
  import chainer
  from chainer import testing
  import numpy
  from chainerrl.links import empirical_normalization
label_desc: Use image node_id 1 for calling the TestEmpiricalNormalization obj's underlying member method code with example usage: obj.test_small_cpu() without return types