{"ast_node_type":"import","tokens":[{"end":104,"kind":"keyword","start":0,"text":"Add"}]}
            Add it to `rustc_data_structures::marker` or use `IntoDynSyncSend` if it's already `Send`")]
#[diagnostic::on_unimplemented(message = "`{Self}` doesn't implement `DynSend`. \
// This is an auto trait for types which can be sent across threads if `sync::is_dyn_thread_safe()`