code: def assert_python_failure(self, *argv):
      exitcode, stdout, stderr = self.run_python(*argv)
      self.assertNotEqual(exitcode, 0)
      return stdout, stderr
  
imports: import contextlib
  import os
  import os.path
  import subprocess
  import sys
  import tempfile
  import threading
  from textwrap import dedent
  import unittest
  from test import support
  from test.support import os_helper
  from test.support import interpreters
label_desc: Use image node_id 7 for calling the TestBase obj's underlying member method code with example usage: obj.assert_python_failure() and returns: stdout,  stderr