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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 filtered_rows_from_args(self, args):
        '''extracts filters from args, rows from manifests, returns filtered rows'''
        if len(self.manifests) == 0:
            print("fw: No manifests downloaded.  Try 'manifest download'")
            return None

        (filters,remainder) = self.filters_from_args(args)
        all = self.all_firmwares()
        rows = self.rows_for_firmwares(all)
        filtered = self.filter_rows(filters, rows)
        return (filtered, remainder)