presto-main/src/main/java/io/prestosql/execution/resourcegroups/InternalResourceGroupManager.java/InternalResourceGroupManager/tryGetPathToRoot
class InternalResourceGroupManager:    @Override
    public Optional<List<ResourceGroupInfo>> tryGetPathToRoot(ResourceGroupId id)
    {
        InternalResourceGroup resourceGroup = groups.get(id);
        return Optional.ofNullable(resourceGroup)
                .map(InternalResourceGroup::getPathToRoot);
    }