code: def __init__(
      self,
      size=10,
      keys=("a", "b", "c"),
      mode=tuple,
      return_array=False,
      callback=None,
      convert=False,
  ):
      if mode is None:
          keys = (keys[0],)
  
      self._keys = keys
      self._mode = mode
      self._return_array = return_array
      self._callback = callback
      self._convert = convert
  
      self.data = np.random.uniform(size=(len(keys), size))
  
file_path: chainer/tests/chainer_tests/dataset_tests/tabular_tests/dummy_dataset.py
imports: import numpy
  import chainer
  from chainer import testing
label_desc: Use image node_id 1 to create a new DummyDataset object from inherited base classes: chainer.dataset with example: obj = DummyDataset(size, keys, mode, return_array, callback, convert)