Initializes the stream.

def run(self):
		""" Initializes the stream. """
		if not hasattr(self, 'queue'):
			raise RuntimeError("Audio queue is not intialized.")

		self.stream.start_stream()
		self.keep_listening = True	
		
		while self.keep_listening:
			try:
				frame = self.queue.get(False, timeout=queue_timeout)
				self.stream.write(frame)
			except Empty:
				continue
			time.sleep(0.01)

		self.stream.stop_stream()
		self.stream.close()
		self.pa.terminate()