title: Thread doesn't stop when I close the GUI it started from
body: <p>I have a UI program that records audio from microphone and speakers with a loop in another thread that writes to file what is recorded, everything goes well until I try to close the GUI, but the thread doesn't stop, as Sublime doesnt show '[Finished in Xs.]'. The thread stops when I click the button 'Stop' tho. This is the main code on the problem:</p>
  <pre><code>thread = Thread(target=self.record_and_recognize, args=(args, callback))
  thread.start()
  def record_and_recognize(self, args, callback_func):
      self.labeltext.set('Recording...')
      with sf.SoundFile(args.filename, mode='w', samplerate=args.samplerate,
                        channels=args.channels, subtype=args.subtype) as file:
              with sd.InputStream(samplerate=args.samplerate, device=args.device,
                                  channels=args.channels, callback=callback_func):
                  # Thread loop that writes sound to file until stopped
                  while self.recording:
                      file.write(self.progression.get())
  </code></pre>
  <p>What can I do?</p>