Function surface_select_smile_delta_wing_strikes 

pub fn surface_select_smile_delta_wing_strikes<S: SurfaceSmile + ?Sized>(
    smile: &S,
    market: &SurfaceMarketContext,
    absolute_delta: f64,
    convention: SurfaceDeltaConvention,
    model: PricingModel,
    policy: SurfaceSmileDeltaSelectionPolicy,
    listed_strikes: &[f64],
) -> Result<SurfaceDeltaWingStrikeSelection, FerroRiskError>