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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 as_backfill_cron_app(cls):
 """a class decorator for Crontabber Apps. This decorator embues a CronApp with the parts necessary to be a backfill CronApp. It adds a main method that forces the base class to use a value of False for 'once'. That means it will do the work of a backfilling app. """

    #----------------------------------------------------------------------
    def main(self, function=None):
        return super(cls, self).main(
            function=function,
            once=False,
        )
    cls.main = main
    cls._is_backfill_app = True
    return cls