Function extract_dupire_local_volatility_grid 

pub fn extract_dupire_local_volatility_grid<S: VolSurface>(
    surface: &S,
    market: &SurfaceMarketContext,
    expiries: &[f64],
    log_moneyness: &[f64],
    policy: &DupireExtractionPolicy,
) -> Result<DupireExtractionGrid, FerroRiskError>