code: def test_empty_dataset_chx(self):
      self.check_empty_dataset(chx)
  
file_path: chainer/tests/chainermn_tests/datasets_tests/test_empty_dataset.py
imports: import unittest
  import numpy
  from chainermn.datasets import create_empty_dataset
  import chainerx
label_desc: Use image node_id 4 for calling the TestEmptyDataset obj's underlying member method code with example usage: obj.test_empty_dataset_chx() without return types