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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 get(self):
 """ Get the current timer value in seconds. Returns: the elapsed time in seconds since the timer started or until the timer was stopped """

        now = datetime.now()
        if self._start_time:
            if self._stop_time:
                return (self._stop_time - self._start_time).total_seconds()
            return (now - self._start_time).total_seconds()
        return 0.