def test_chainDeferredRecordsExplicitChain(self):
        a = defer.Deferred()
        b = defer.Deferred()
        b.chainDeferred(a)
        self.assertIdentical(a._chainedTo, b)
One market param per engine is mandatory
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/test/test_defer.py/DeferredTestCase.test_chainDeferredRecordsExplicitChain--crossover with--dataset/ETHPy150Open jcbagneris/fms/tests/utils.py/YamlParserTests.testMarketMandatory