class_docstr: Ensure all opt presets contain descriptions.
code: def test_opt_preset_docs(self):
      from parlai.opt_presets.docs import PRESET_DESCRIPTIONS
  
      folder = os.path.dirname(opt_presets.__file__)
      has_file = set(
          x[len(folder) + 1 : -4]
          for x in glob.glob(f"{folder}/*/*.opt")
      )
      has_docs = set(PRESET_DESCRIPTIONS.keys())
  
      file_no_docs = has_file - has_docs
      if file_no_docs:
          raise AssertionError(
              "The following opt presets have files but no documentation: "
              f"{', '.join(file_no_docs)}"
          )
      docs_no_file = has_docs - has_file
      if docs_no_file:
          raise AssertionError(
              "The following opt presets have documentation but no files: "
              f"{', '.join(docs_no_file)}"
          )
  
file_path: ParlAI/tests/test_code.py
imports: import pytest
  import glob
  import unittest
  import os
  import parlai.utils.testing
  import parlai.opt_presets
label_desc: Use image node_id 1 for calling the TestOptPresets obj's underlying member method code with example usage: obj.test_opt_preset_docs() without return types