def __getslice__(self, start, stop):
        return self._children[start:stop]
Allow changing of the policy before we get started
dataset/ETHPy150Open flosch/simpleapi/example_project/client/python/sapi/message.py/MessageElement.__getslice__--crossover with--dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/tests/unit/policy_fixture.py/RealPolicyFixture._prepare_policy