code: def test_split_dataset_head(self):
      original = [1, 2, 3, 4, 5]
      subset1, subset2 = datasets.split_dataset(original, 0)
      self.assertEqual(len(subset1), 0)
      self.assertEqual(len(subset2), 5)
  
imports: import unittest
  from chainer import datasets
  from chainer import testing
label_desc: Use image node_id 2 for calling the TestSplitDataset obj's underlying member method code with example usage: obj.test_split_dataset_head() without return types