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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 countdown_set(self, duration, start_now):
 """ set the countdown :param str duration: :param str start_now: """

        log.debug("countdown => set...")
        params = {'duration': duration, 'start_now': start_now}
        self._app_exec(
            "com.lametric.countdown", "countdown.configure", params
        )