Nested hashmap

example.rs

   let mut scores: HashMap<String, HashMap<String, u32>> = HashMap::new();
    1     for repo in tracked_repos {
    2         let contributions: Vec<Contribution> = gh
    3             .get_contributors(&repo)
    4             .expect("unable to get contributors for repo")
    5             .iter()
    6             .filter(|c| participants_set.contains(&c.login))
    7             .cloned()
    8             .collect();
    9         for contrib in contributions {
   10             let login = contrib.login.to_string();
   11             scores
   12                 .entry(login.clone())
   13                 .and_modify(|nested| {
   14                     nested.insert(repo.clone(), contrib.contributions);
   15                 })
   16                 .or_insert_with(|| {
   17                     let mut new_map: HashMap<String, u32> = HashMap::new();
   18                     new_map.insert(repo.clone(), contrib.contributions);
   19                     new_map
   20                 });
   21         }
   22     }