def failUnlessIsInstance(self, instance, classOrTuple):
        if not isinstance(instance, classOrTuple):
            self.fail("%r is not an instance of %s" % (instance, classOrTuple))
returns the best pool or pools we have
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/trial/unittest.py/_Assertions.failUnlessIsInstance--crossover with--dataset/ETHPy150Open c00w/bitHopper/bitHopper/Logic/ServerLogic.py/filter_best