title: How to write `app.yaml` file for Google App Engine app?
body: <p>I registered a Google App Engine app and I have some files below:</p>
  
  <ul>
  <li><code>/index.html</code></li>
  <li><code>/tabs.css</code></li>
  <li><code>/tab.js</code></li>
  <li><code>/temp.py</code></li>
  </ul>
  
  <p>How should I write the <code>app.yaml</code> file?</p>