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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 age(self, **kwargs):
 """ Age this particle. parameters (optional, only one allowed):
 days (default) hours minutes seconds """

        if kwargs.get('days', None) is not None:
            self._age += kwargs.get('days')
            return
        if kwargs.get('hours', None) is not None:
            self._age += kwargs.get('hours') / 24.
            return
        if kwargs.get('minutes', None) is not None:
            self._age += kwargs.get('minutes') / 24. / 60.
            return
        if kwargs.get('seconds', None) is not None:
            self._age += kwargs.get('seconds') / 24. / 60. / 60.
            return

        raise KeyError("Could not age particle, please specify 'days', 'hours', 'minutes', or 'seconds' parameter")