code: def test_simple_read_from_a_single_file(
      scalar_dataset, reader_factory
  ):
      """See if we can read data when a single parquet file is specified instead of a parquet directory"""
      assert scalar_dataset.url.startswith("file://")
      path = scalar_dataset.url[len("file://") :]
      one_parquet_file = glob.glob(f"{path}/**.parquet")[0]
  
      with reader_factory(f"file://{one_parquet_file}") as reader:
          all_data = list(reader)
          assert len(all_data) > 0
  
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 4 for calling a global function with example usage: test_simple_read_from_a_single_file(scalar_dataset, reader_factory) without return types