title: Restore __builtins__ to default
body: <p>If I code a mistake and I do something like this:</p>
  
  <pre><code>__builtins__ = 'abcd'
  </code></pre>
  
  <p>and before I didn't code <code>import builtins</code> is there a way to restore <code>__builtins__</code> to its default value?</p>