code: def test_shuffled_fields(dataset_num_files_1, reader_factory):
      """Test to verify not sorted keys for fields argument in ngrams work."""
      fields = {
          2: [
              TestSchema.id,
              TestSchema.id2,
              TestSchema.image_png,
              TestSchema.matrix,
          ],
          -1: [TestSchema.id, TestSchema.id2, TestSchema.sensor_name],
      }
      _test_continuous_ngram_tf(
          fields, dataset_num_files_1, reader_factory
      )
  
imports: from decimal import Decimal
  import numpy
  import pytest
  import tensorflow.compat.v1
  from unittest import mock
  from petastorm import make_reader
  from petastorm.ngram import NGram
  from petastorm.tests.conftest import SyntheticDataset, maybe_cached_dataset
  from petastorm.tests.test_common import create_test_dataset, TestSchema
  from petastorm.tests.test_tf_utils import create_tf_graph
  from petastorm.tf_utils import tf_tensors
label_desc: Use image node_id 27 for calling a global function with example usage: test_shuffled_fields(dataset_num_files_1, reader_factory) without return types