class_docstr: Run tests in a subprocess
      
class_docstr_tok: ["Run","tests","in","a","subprocess"]
code: def wait(self):
      self.process.wait()
      self.stdout_capturer.halt()
      self.stdout = self.stdout_capturer.get_buffer()
      return self.process.returncode
  
imports: from __future__ import print_function
  import argparse
  import json
  import multiprocessing.pool
  import os
  import stat
  import re
  import requests
  import shutil
  import signal
  import sys
  import subprocess
  import time
  from .iptest import have, test_group_names, test_sections, StreamCapturer, test_for
  from IPython.utils.path import compress_user
  from IPython.utils.py3compat import bytes_to_str
  from IPython.utils.sysinfo import get_sys_info
  from IPython.utils.tempdir import TemporaryDirectory
  from IPython.utils.text import strip_ansi
label_desc: Use image node_id 4 for calling the TestController obj's underlying member method code with example usage: obj.wait() and returns: self