pub fn get_sparse_poss<T>(
basepair_probs_pair: &(&HashMap<(T, T), f32>, &HashMap<(T, T), f32>),
match_probs: &HashMap<(T, T), f32>,
seq_len_pair: &(T, T),
) -> (HashMap<(T, T), HashSet<(T, T)>>, HashMap<(T, T), HashSet<(T, T)>>, HashSet<(T, T, T, T)>, HashMap<(T, T), HashSet<(T, T)>>, HashMap<T, HashSet<T>>, HashMap<T, HashSet<T>>)where
T: HashIndex,