{"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"trait_ref.trait_id"}]}
                    trait_ref.trait_id = to_chalk_trait_id(fn_x_trait);
                    let fn_x_trait = fn_x.get_id(self.db, krate)?;
                    let obligation: chalk_ir::InEnvironment<chalk_ir::Goal<Interner>> =