code: def test_invalid_and_valid_column_names(
      scalar_dataset, reader_factory
  ):
      """Request one column that doesn't exist and one that does. Confirm that only get one field back and
      that get exception when try to read from invalid field."""
      all_fields = list(scalar_dataset.data[0].keys())
      bad_field = _get_bad_field_name(all_fields)
      requested_fields = [bad_field, all_fields[1]]
  
      with reader_factory(
          scalar_dataset.url, schema_fields=requested_fields
      ) as reader:
          sample = next(reader)._asdict()
          assert len(sample) == 1
          assert bad_field not in sample
  
imports: import glob
  import itertools
  import numpy
  import pandas
  import pytest
  from pyarrow import parquet
  from petastorm import make_batch_reader, make_reader
  from petastorm.arrow_reader_worker import ArrowReaderWorker
  from petastorm.tests.test_common import create_test_scalar_dataset
  from petastorm.transform import TransformSpec
  from petastorm.unischema import UnischemaField
label_desc: Use image node_id 10 for calling a global function with example usage: test_invalid_and_valid_column_names(scalar_dataset, reader_factory) without return types