def setup_cache(self, backend='mongo', database=None, use_compression=True,
                    **kwargs):
        if database is None:
            raise SpiderMisuseError('setup_cache method requires database '
                                    'option')
        self.cache_enabled = True
        mod = __import__(backend % 'grab.spider.cache_backend.%s',
                         globals(), locals(), ['foo'])
        cache = mod.CacheBackend(database=database,
                                 use_compression=use_compression,
                                 spider=self, **kwargs)
        self.cache_pipeline = CachePipeline(self, cache)
dataset/ETHPy150Open lorien/grab/grab/spider/base.py/Spider.setup_cache/swapped operands of `%`