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<title>Document</title>
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<ul class="nav">
<li>榴莲</li>
<li>臭豆腐</li>
<li>鲱鱼罐头</li>
<li>大猪蹄子</li>
</ul>
<script>
// 闭包应用 - 3秒钟之后，打印所有li 元素的内容
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}, 3000)
})(i);
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