code: def test_on_itself(each_version):
      """
      There are obviously no syntax erros in the Python code of parso. However
      parso should output the same for all versions.
      """
      grammar = parso.load_grammar(version=each_version)
      path = os.path.dirname(os.path.dirname(__file__)) + "/parso"
      for file in get_python_files(path):
          tree = grammar.parse(path=file)
          errors = list(grammar.iter_errors(tree))
          assert not errors
  
imports: import os
  import parso
label_desc: Use image node_id 2 for calling a global function with example usage: test_on_itself(each_version) without return types