Function reverse_traverse 

pub fn reverse_traverse<N, E, F, Err>(
    graph: &StableGraph<N, E>,
    callback: F,
) -> Result<(), Err>
where
    N: Clone,
    E: Clone,
    F: FnMut(GraphQuery<'_, N, E>, NodeIndex) -> Result<(), Err>,

Call the supplied callback for each node in the given graph in reverse topological order.