xpath提取标签和内容

转：https://segmentfault.com/q/1010000012110138/a-1020000012113020

<div>
   <table>
      <tr>
         <td class="td class">Row value 1</td>
         <td class="td class">Row value 2</td>
      </tr>
      <tr>
         <td class="td class">Row value 3</td>
         <td class="second td class">Row value 4</td>
      </tr>
      <tr>
         <td class="third td class">Row value 1</td>
         <td class="td class">Row value 1</td>
      </tr>
   </table>
</div>

如何把table标签提取出来，结果如下：

<table>
  <tr>
     <td class="td class">Row value 1</td>
     <td class="td class">Row value 2</td>
  </tr>
  <tr>
     <td class="td class">Row value 3</td>
     <td class="second td class">Row value 4</td>
  </tr>
  <tr>
     <td class="third td class">Row value 1</td>
     <td class="td class">Row value 1</td>
  </tr>
</table>

代码如下：

tree = etree.HTML(html)
content = tree.xpath('//div/table')[0]
print(content)

# <Element div at 0x1bce7463548>
# 即：如何将Element对象转成str类型