```html
<!DOCTYPE html>
<html>
  <head>
    <title>test</title>
    <script src="https://unpkg.com/vue"></script>
  </head>
  <body>
    <div id="app">
      <p v-show="show">test</p>
      <button v-on:click="change">btn</button>
    </div>

    <script>
      var app = new Vue({
        el: "#app",
        data: {
          show: true
        },
        methods: {
          change: function () {
            this.show = false;
            setTimeout("", 5000);
            this.show = true;
          }
        }
      });
    </script>
  </body>
</html>

```

Why does the element not hide for 5 seconds after pressing the button and then show again?
And how can I change the code to achieve this function?