def test_maybeDeferredAsync(self):
        d = defer.Deferred()
        d2 = defer.maybeDeferred(lambda: d)
        d.callback('Success')
        return d2.addCallback(self.assertEquals, 'Success')
L{defer.maybeDeferred} should let L{defer.Deferred} instance pass by
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/test/test_defer.py/DeferredTestCase.test_maybeDeferredAsync