class_docstr: A `Dataset` that groups its input and performs a windowed reduction.
code: def _functions(self):
      return [self._key_func, self._reduce_func, self._window_size_func]
  
file_path: tensorflow-upstream/tensorflow/python/data/ops/group_by_window_op.py
imports: from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.data.ops import structured_function
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor_spec
  from tensorflow.python.ops import gen_experimental_dataset_ops
label_desc: Use image node_id 6 for calling the _GroupByWindowDataset obj's underlying member method code with example usage: obj._functions() and returns: list