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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 screen. INPUT stats: Stats database to display duration: duration of the loop cs_status: "None": standalone or server mode "Connected": Client is connected to the server "Disconnected": Client is disconnected from the server return_to_browser: True: Do not exist, return to the browser list False: Exit and return to the shell OUTPUT True: Exit key has been pressed """

        # Flush display
        self.flush(stats, cs_status=cs_status)

        # If the duration is < 0 (update + export time > refresh_time)
        # Then display the interface and log a message
        if duration <= 0:
            logger.warning('Update and export time higher than refresh_time.')
            duration = 0.1

        # Wait duration (in s) time
        exitkey = False
        countdown = Timer(duration)
        # Set the default timeout (in ms) for the getch method
        self.term_window.timeout(int(duration * 1000))
        while not countdown.finished() and not exitkey:
            # Getkey
            pressedkey = self.__catch_key(return_to_browser=return_to_browser)
            # Is it an exit key ?
            exitkey = (pressedkey == ord('\x1b') or pressedkey == ord('q'))
            if not exitkey and pressedkey > -1:
                # Redraw display
                self.flush(stats, cs_status=cs_status)
                # Overwrite the timeout with the countdown
                self.term_window.timeout(int(countdown.get() * 1000))

        return exitkey