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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 find_all(self, query):
 """A procedure to assist in finding or detailing specific backups Currently supports: * a backup name (base_number_number) * the psuedo-name LATEST, which finds the backup with the most recent modification date """


        match = re.match(storage.BASE_BACKUP_REGEXP, query)

        if match is not None:
            for backup in iter(self):
                if backup.name == query:
                    yield backup
        elif query == 'LATEST':
            all_backups = list(iter(self))

            if not all_backups:
                return

            assert len(all_backups) > 0

            all_backups.sort(key=lambda bi: bi.last_modified)
            yield all_backups[-1]
        else:
            raise exception.UserException(
                msg='invalid backup query submitted',
                detail='The submitted query operator was "{0}."'
                .format(query))