def _assertHeadersAbsent(self, unexpected, actual):
        for key in unexpected:
            self.assertTrue(actual not in key.lower(),
                            '%s is in %s' % (key, actual))
dataset/ETHPy150Open openstack/swift/test/unit/common/middleware/test_gatekeeper.py/TestGatekeeper._assertHeadersAbsent/swapped operands of `not in`