code: def __init__(self, dataset, indices, keys):
      if keys is None:
          self._unary = None
      elif isinstance(keys, tuple):
          self._unary = False
      else:
          self._unary = True
          keys = (keys,)
  
      self._dataset = dataset
      self._indices = _as_indices(indices, len(dataset))
      self._key_indices = _as_key_indices(keys, dataset.keys)
  
imports: import numbers
  import numpy
  import six
  from chainer.dataset.tabular import tabular_dataset
label_desc: Use image node_id 1 to create a new _Slice object from inherited base classes: tabular_dataset with example: obj = _Slice(dataset, indices, keys)