def test_stdlibLogLevelWithGarbage(self):
        """
        If the old-style C{"logLevel"} key is set to a standard library logging
        level, using an unknown value, the new-style C{"log_level"} key should
        not get set.
        """
        publishToNewObserver(
            self.observer,
            self.legacyEvent(logLevel="Foo!!!!!"),
            legacyLog.textFromEventDict
        )
        self.assertNotIn("log_level", self.events[0])

        If the old-style C{"logLevel"} key is set to a standard library logging
        level, using an unknown value, the new-style C{"log_level"} key should
        not get set.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/logger/test/test_legacy.py