Method lookup

src/models/common.rs:532–539

(&self, k: &K)

    }

    pub fn lookup(&self, k: &K) -> Option<V>
    where
        V: Clone,
    {
        let index = self.hash_key(k);
        let ht = self.hash_table_list[index].lock().unwrap();
        ht.get(k).cloned()
    }

    pub fn mutate<F>(&self, k: K, f: F)
    where