let self_param = match (binding_mode, mutbl) {
(Mode::Ref(None), Mutability::Mut) => "&mut self".to_string(),
(Mode::Ref(Some(lifetime)), Mutability::Mut) => {
let self_param = match (binding_mode, mutbl) {
(Mode::Ref(None), Mutability::Mut) => "&mut self".to_string(),
(Mode::Ref(Some(lifetime)), Mutability::Mut) => {