def key(self, itemId):
        return self.itemIdMapper.key(itemId)
Copies this to a descriptor_pb2.DescriptorProto.
dataset/ETHPy150Open rwl/muntjac/muntjac/ui/tree.py/Tree.key--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/google/net/proto2/python/public/descriptor.py/Descriptor.CopyToProto