无法点击下一页链接？

Question

如何使用scrapy python迭代下一页链接

Html代码：

<span class="pager-links">
<a href="search-results?p=1"> 1</a>
<span> 2</span>
<a href="/search-results?p=3"> 3</a>
<a href="/search-results?p=4"> 4</a>
<a href="/search-results?p=5"> 5</a>
</span>
<a class="nav next" href="/search-results?p=3"> </a> // This is for to click the next page link.
<a class="nav last" href="//search-results?p=327"> </a>