def isExpanded(self, itemId):
        return itemId in self._expanded
Helper function to validate that performing given operation for given
dataset/ETHPy150Open rwl/muntjac/muntjac/ui/tree.py/Tree.isExpanded--crossover with--dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/functional/test_ebs.py/VolumeStateTransitionTests._process_volume