Function executor_scope 

pub fn executor_scope<F, T>(f: F) -> impl Future<Output = T>
where
    F: for<'scope> AsyncFnOnce(&ScopeExecutor<'scope, BuiltinExecutor>) -> T,

Run an async closure with a scoped Executor wrapper that forwards spawns to this executor, waits for all spawned tasks to finish when the closure returns, and aborts any outstanding tasks if the scope future itself is cancelled.