{"ast_node_type":"other","tokens":[{"end":62,"kind":"keyword","start":0,"text":"self.tcx.def_span(self.parent_def_id),"}]}
                        self.tcx.def_span(self.parent_def_id),
                    self.tcx.dcx().span_delayed_bug(
                        format!("unsupported bound variable kind: {arg:?}"),