Function kgdata::mapreduce::functions::make_begin_try_flat_map_fn

pub fn make_begin_try_flat_map_fn<I, E, F, OPI>(
    func: F
) -> impl Fn(I) -> Vec<Result<OPI::Item, E>>
where
    F: Fn(I) -> Result<OPI, E>,
    OPI: IntoIterator,
    E: Send,