def test_invalidEndResponse(self):
        """
        If an END is received in response to an operation that isn't C{get},
        C{gets}, or C{stats}, an error is raised in
        L{MemCacheProtocol.dataReceived}.
        """
        self.proto.set(b"key", b"value")
        self.assertRaises(
            RuntimeError, self.proto.dataReceived,
            b"END\r\n")

        If an END is received in response to an operation that isn't C{get},
        C{gets}, or C{stats}, an error is raised in
        L{MemCacheProtocol.dataReceived}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_memcache.py