code: def test_negative_lookahead(self) -> None:
      grammar_source = """
          start: NAME !NAME expr NEWLINE? ENDMARKER
          expr: NAME | NUMBER
          """
      test_source = """
          valid_cases = ["foo 34"]
          invalid_cases = ["foo bar"]
          self.check_input_strings_for_grammar(valid_cases, invalid_cases)
          """
      self.run_test(grammar_source, test_source)
  
imports: import contextlib
  import subprocess
  import sysconfig
  import textwrap
  import unittest
  import os
  import shutil
  import tempfile
  from pathlib import Path
  from test import test_tools
  from test import support
  from test.support import os_helper, import_helper
  from test.support.script_helper import assert_python_ok
label_desc: Use image node_id 8 for calling the TestCParser obj's underlying member method code with example usage: obj.test_negative_lookahead() without return types