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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def update(self, stats, duration=3, cs_status=None, return_to_browser=False):
 """Update the servers' list screen. Wait for __refresh_time sec / catch key every 100 ms. stats: Dict of dict with servers stats """

        # Flush display
        logger.debug('Servers list: {}'.format(stats))
        self.flush(stats)

        # Wait
        exitkey = False
        countdown = Timer(self.__refresh_time)
        while not countdown.finished() and not exitkey:
            # Getkey
            pressedkey = self.__catch_key(stats)
            # Is it an exit or select server key ?
            exitkey = (
                pressedkey == ord('\x1b') or pressedkey == ord('q') or pressedkey == 10)
            if not exitkey and pressedkey > -1:
                # Redraw display
                self.flush(stats)
            # Wait 100ms...
            self.wait()

        return self.active_server