code: def test_recombine_set_tokens_invalid(self):
      tokens = (
          ["{", "1", ", ", "2"],
          ['"F"', ", ", '"C"', ", ", '"N"', "}", ", ", "optional"],
          ["{", "1", ", ", "2", ", ", "default", ": ", "None"],
      )
      combined_tokens = (
          ["{1, 2"],
          ['"F"', ", ", '"C"', ", ", '"N"', "}", ", ", "optional"],
          ["{1, 2", ", ", "default", ": ", "None"],
      )
  
      for tokens_, expected in zip(tokens, combined_tokens):
          actual = _recombine_set_tokens(tokens_)
          assert expected == actual
  
imports: import re
  from collections import namedtuple
  from inspect import cleandoc
  from textwrap import dedent
  from unittest import mock
  import pytest
  from sphinx.ext.napoleon import Config
  from sphinx.ext.napoleon.docstring import GoogleDocstring, NumpyDocstring, _convert_numpy_type_spec, _recombine_set_tokens, _token_type, _tokenize_type_spec
  from tests.test_extensions.ext_napoleon_pep526_data_google import PEP526GoogleClass
  from tests.test_extensions.ext_napoleon_pep526_data_numpy import PEP526NumpyClass
label_desc: Use image node_id 20 for calling the TestNumpyDocstring obj's underlying member method code with example usage: obj.test_recombine_set_tokens_invalid() without return types