class_docstr: Tests initialization and instance methods of the ``Dataset`` class.
docstr: Test that __getattr__ returns UNSET if a dataset field
  is not set.
docstr_tok: ["Test","that","__getattr__","returns","UNSET","if","a","dataset","field","is","not","set","."]
code: def test_getattr_unset_fields(self):
      """Test that __getattr__ returns UNSET if a dataset field
      is not set."""
  
      my_dataset = MyDataset(x="a", y="b")
      assert my_dataset.description is UNSET
  
imports: from numbers import Number
  from pathlib import Path
  from typing import ClassVar, Dict
  import numpy
  import pytest
  from pennylane.data import AttributeInfo, Dataset, DatasetJSON, DatasetNotWriteableError, DatasetScalar, attribute, field
  from pennylane.data.base.dataset import UNSET, _init_arg
  from pennylane.data.base.hdf5 import open_group
label_desc: Use image node_id 6 for calling the TestDataset obj's underlying member method code with example usage: obj.test_getattr_unset_fields() without return types