title: clojure: how to pick up one item with the most high value from a map
body: <p>I have the following map. And give a parameter of sex, need to pickup the user without the most money for that sex. How to do it?</p>
  
  <pre><code>{:user1 {:money 400 :sex :male}
  :user2 {:money 300 :sex :female}
  :user3 {:money 200 :sex :male}
  }
  </code></pre>