def test_trace(self):
        def publisher(event):
            observer(event)

        def observer(event):
            self.assertEqual(event["log_trace"], [(log, publisher)])

        log = TestLogger(observer=publisher)
        log.info("Hello.", log_trace=[])
Returns a string suitable for RFC 2822 compliant Message-ID, e.g:
dataset/ETHPy150Open twisted/twisted/twisted/logger/test/test_logger.py/LoggerTests.test_trace--crossover with--dataset/ETHPy150Open CollabQ/CollabQ/vendor/django/core/mail.py/make_msgid