HepMC::GenEventBarcodes Node1 HepMC::GenEventBarcodes - m_vertexBC - m_particleBC + from_string() + to_string() + barcode_to_vertex() + barcode_to_vertex() + barcode_to_particle() + barcode_to_particle() + add() + remove() + add() + remove() + barcode_to_vertex_map() + barcode_to_particle _map() + id_to_barcode_map() + fillAttribute() Node2 HepMC3::Attribute     Node2->Node1