Function create_value_container_signals 

pub fn create_value_container_signals<T>(
    producer: impl Fn() -> T + 'static,
) -> (RwSignal<T>, RwSignal<T>)
where
    T: Clone + 'static,

A convenience function that creates two signals for use in a value_container

• The outbound signal enables a widget’s internal input event handlers to publish state changes via ValueContainer::on_update.
• The inbound signal propagates value changes in the producer function into a widget’s internals.