def test_regular_fields(self):
        class MyException(Exception):
            pass
        register_exception_extractor(MyException,
                                     lambda e: {"key": e.args[0]})
        exception = MyException("because")
        messages = get_traceback_messages(exception)
        assertContainsFields(self, messages[0],
                             {"message_type": "eliot:traceback",
                              "reason": exception,
                              "exception": MyException})
Sequence and other must be composed of (Key, Value) pairs. If self.sequence contains (K, V)
dataset/ETHPy150Open ClusterHQ/eliot/eliot/tests/test_traceback.py/TracebackExtractionTests.test_regular_fields--crossover with--dataset/ETHPy150Open EntilZha/PyFunctional/functional/pipeline.py/Sequence.outer_join