/// Create a new backend factory.
Create a new backend factory.
Create a new backend factory .
pub fn new(backend: T) -> Self {
        Self {
            state: State::Uninitialized,
            backend,
        }
    }
pub fn new ( backend : T ) -> Self { Self { state : State :: Uninitialized , backend , } }
Create a new backend factory.
Create a new backend factory .
backend
T