{"ast_node_type":"other","tokens":[{"end":50,"kind":"keyword","start":0,"text":"[std::sync::MutexGuard<'_,"}]}
    [std::sync::MutexGuard<'_, T> where T: ?Sized]
    [std::rc::Weak<T, A> where T: ?Sized, A: Allocator]
    [std::sync::RwLockReadGuard<'_, T> where T: ?Sized]