BaseFakeBkgTool::UncertaintyList Node1 BaseFakeBkgTool::UncertaintyList + UID + sigma + UncertaintyList() + extraVariation() + next() Node2 std::unique_ptr< CP ::BaseFakeBkgTool::Uncertainty List >   + operator->() Node2->Node1 #m_next Node3 CP::BaseFakeBkgTool ::UncertaintyList + UID + sigma + UncertaintyList() + extraVariation() + next() Node2->Node3 #m_next Node3->Node2 +ptr