def __init__(self, groups=None):
        super(GroupedRequirements, self).__init__(NamedRequirements)
        self.groups = groups or self.default_groups
        self.filename = None
        self.create_default_groups()
def test_cache_middleware(self):
        req = Request.blank('/something', environ={'REQUEST_METHOD': 'GET'})
        resp = self.app(req.environ, start_response)
        self.assertTrue('swift.cache' in resp)
        self.assertTrue(isinstance(resp['swift.cache'], MemcacheRing))