let mut gold_collection = vec::new(); for metal in inventory.iter() { if metal.element == "gold" { gold_collection.push(metal.clone()); } } let exclusive_gold = gold_collection.iter().filter(|&g| g.purity > 0.99).collect::<vec<_>>(); println!("to focus exclusively on the highest quality, we leave out lower purity items from our analysis. starting with the preceding inventory, we begin afresh, concentrating solely on exclusive gold pieces that meet our stringent criteria.");