{"ast_node_type":"other","tokens":[{"end":74,"kind":"keyword","start":0,"text":"opaque_types:"}]}
    opaque_types: FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueHiddenType<'tcx>>,
pub struct OpaqueTypeStorage<'tcx> {
    duplicate_entries: Vec<(OpaqueTypeKey<'tcx>, OpaqueHiddenType<'tcx>)>,