def __getstate__(self):
        state = super(VariableTree, self).__getstate__()
        if self._parent_ref is not None:
            state['_parent_ref'] = self._parent_ref()
        return state
Execute a test for the given domain at a random location.
dataset/ETHPy150Open OpenMDAO/OpenMDAO-Framework/openmdao.main/src/openmdao/main/vartree.py/VariableTree.__getstate__--crossover with--dataset/ETHPy150Open StackStorm/st2contrib/packs/webpagetest/actions/lib/webpagetest.py/WebPageTestAction.test_random_location