def _create_maxmind_strategy(self, maxmind_params):
        db_snapshot_strings = maxmind_params['db_snapshots']
        if len(db_snapshot_strings) == 0:
            raise ValueError('IPTranslationStrategyNoDatesSpecified')

        maxmind_dir = maxmind_params['maxmind_dir']
        snapshots = []
        for db_snapshot_string in db_snapshot_strings:
            snapshot_datetime = datetime.datetime.strptime(db_snapshot_string,
                                                           '%Y-%m-%d')
            snapshot_path = IPTranslationStrategyMaxMind.get_maxmind_snapshot_path(
                snapshot_datetime, maxmind_dir)
            try:
                snapshot_file = self._file_opener(snapshot_path, 'rb')
                snapshot = (snapshot_datetime, snapshot_file)
                snapshots.append(snapshot)
            except __HOLE__ as io_error:
                raise MissingMaxMindError(snapshot_path, io_error)

        return IPTranslationStrategyMaxMind(snapshots)
dataset/ETHPy150Open m-lab/telescope/telescope/iptranslation.py/IPTranslationStrategyFactory._create_maxmind_strategy