code: def test_reading_legacy_dataset(legacy_dataset_url):
      """The test runs for a single legacy dataset. Opens the dataset using `make_reader` and reads all records from it"""
      with make_reader(legacy_dataset_url, workers_count=1) as reader:
          all_data = list(reader)
  
          # Some basic check on the data
          assert len(all_data) == 100
          assert len(all_data[0]._fields) > 5
          assert all_data[0].matrix.shape == (32, 16, 3)
  
imports: import os
  import pytest
  from petastorm import make_reader
label_desc: Use image node_id 2 for calling a global function with example usage: test_reading_legacy_dataset(legacy_dataset_url) without return types