code: def test_dict_callable_unary_callable_unary(self):
      dataset = tabular.from_data(
          {"a": lambda i: i * i, "b": lambda i: -i}, size=10
      )
  
      self.assertIsInstance(dataset, chainer.dataset.TabularDataset)
      self.assertEqual(len(dataset), 10)
      self.assertEqual(set(dataset.keys), {"a", "b"})
      self.assertEqual(dataset.mode, dict)
  
      output = dataset.slice[[1, 3]].fetch()
      np.testing.assert_equal(output, {"a": [1, 9], "b": [-1, -3]})
      self.assertIsInstance(output["a"], list)
      self.assertIsInstance(output["b"], list)
  
imports: import unittest
  import numpy
  import chainer
  from chainer.dataset import tabular
  from chainer import testing
label_desc: Use image node_id 23 for calling the TestFromData obj's underlying member method code with example usage: obj.test_dict_callable_unary_callable_unary() without return types