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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 refresh(self):
 """ explicitely refresh user interface; useful when changing widgets dynamically """

        logger.debug("refresh user interface")
        try:
            with self.refresh_lock:
                self.draw_screen()
        except AssertionError:
            logger.warning("application is not running")
            pass