求教一个js简易问题

Question

<p title="a gentle reminder">don't forget to buy this stuff.</p>

<ul id="purchases">

    <li title="one">a tin of beans</li>

    <li class="sale" title="two">cheese</li>

    <li class="sale important">milk</li>

</ul>

<script>

    var shopping = document.getElementsById("purchases");

    var items = shopping.getElementsByTagName("*");

    alert (items.length);

</script>

Answer 1

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