code: def test_iter(self):
      dataset = dummy_dataset.DummyDataset(
          mode=self.mode, return_array=self.return_array
      )
      it = iter(dataset)
      for i in range(10):
          if self.mode is tuple:
              expected = tuple(dataset.data[:, i])
          elif self.mode is dict:
              expected = dict(zip(("a", "b", "c"), dataset.data[:, i]))
          elif self.mode is None:
              expected = dataset.data[0, i]
  
          self.assertEqual(next(it), expected)
  
      with self.assertRaises(StopIteration):
          next(it)
  
file_path: chainer/tests/chainer_tests/dataset_tests/tabular_tests/test_tabular_dataset.py
imports: import unittest
  import numpy
  from chainer import testing
  from chainer_tests.dataset_tests.tabular_tests import dummy_dataset
label_desc: Use image node_id 4 for calling the TestTabularDataset obj's underlying member method code with example usage: obj.test_iter() without return types