title: Translate `thread.start_new_thread(...)` to the new threading API
body: <p>When I use the old Python <code>thread</code> API everything works fine:</p>
  
  <pre><code>thread.start_new_thread(main_func, args, kwargs)
  </code></pre>
  
  <p>But if I try to use the new <a href="http://docs.python.org/library/threading.html#thread-objects" rel="noreferrer">threading</a> API the process, which runs the thread hangs when it should exit itself with <code>sys.exit(3)</code>:</p>
  
  <pre><code>threading.Thread(target=main_func, args=args, kwargs=kwargs).start()
  </code></pre>
  
  <p>How can I translate the code to the new threading API?</p>
  
  <p>You can see this example in <a href="http://code.djangoproject.com/browser/django/trunk/django/utils/autoreload.py#L89" rel="noreferrer">context</a>.</p>