code: def dataset_urls():
      """Returns a list of legacy datasets available for testing"""
      legacy_data_directory = os.path.join(
          os.path.dirname(__file__), "data", "legacy"
      )
      versions = os.listdir(legacy_data_directory)
      urls = [
          "file://" + os.path.join(legacy_data_directory, v)
          for v in versions
      ]
      return urls
  
imports: import os
  import pytest
  from petastorm import make_reader
label_desc: Use image node_id 1 for calling a global function with example usage: dataset_urls() and returns: urls