diff --git a/include/gemmi/topo.hpp b/include/gemmi/topo.hpp
index 1848666a..90c2de4d 100644
--- a/include/gemmi/topo.hpp
+++ b/include/gemmi/topo.hpp
@@ -308,7 +308,7 @@ GEMMI_DLL std::unique_ptr<Topo>
 prepare_topology(Structure& st, MonLib& monlib, size_t model_index,
                  HydrogenChange h_change, bool reorder,
                  std::ostream* warnings=nullptr, bool ignore_unknown_links=false,
-                 bool use_cispeps=false, bool update_all_atom_names=false);
+                 bool use_cispeps=false, bool update_old_atom_names=false);
 
 
 GEMMI_DLL std::unique_ptr<ChemComp> make_chemcomp_with_restraints(const Residue& res);
diff --git a/python/topo.cpp b/python/topo.cpp
index 709b4f56..4de52829 100644
--- a/python/topo.cpp
+++ b/python/topo.cpp
@@ -176,7 +176,8 @@ void add_topo(py::module& m) {
         warnings = &os;
       }
       return prepare_topology(st, monlib, model_index, h_change, reorder,
-                              warnings, ignore_unknown_links, use_cispeps);
+                              warnings, ignore_unknown_links, use_cispeps,
+                              update_old_atom_names);
     }, py::arg("st"), py::arg("monlib"), py::arg("model_index")=0,
        py::arg("h_change")=HydrogenChange::NoChange, py::arg("reorder")=false,
        py::arg("warnings")=py::none(), py::arg("ignore_unknown_links")=false,