def METHOD_NAME(self):
    x = yield process_chain_both(
        [cb_fail, cb2, cb3], [None, eb1, None], "res", "v1", "v2"
    )
    self.assertEqual(x, "(cb3 (eb1 TypeError v1 v2) v1 v2)")
    fail = Failure(ZeroDivisionError())
    x = yield process_chain_both(
        [eb1, cb2, cb3], [eb1, None, None], fail, "v1", "v2"
    )
    self.assertEqual(x, "(cb3 (cb2 (eb1 ZeroDivisionError v1 v2) v1 v2) v1 v2)")