##### parsel.示例
```python
from parsel import Selector
text = """
<html>
<body>
<h1>Hello, Parsel!</h1>
<ul>
<li><a href="http://example.com">Link 1</a></li>
<li><a href="http://scrapy.org">Link 2</a></li>
</ul>
<script type="application/json">{"a": ["b", "c"]}</script>
</body>
</html>"""
selector = Selector(text=text)
# 选择器
selector.css('h1::text').get()
# css 选择器
# 'Hello, Parsel!'
selector.xpath('//h1/text()').re(r'\w+')
# xpath 选择器
# ['Hello', 'Parsel']
for li in selector.css('ul > li'):
print(li.xpath('.//@href').get())
# css 选择器
# http://example.com
# http://scrapy.org
selector.css('script::text').jmespath("a").get()
# JMESPath 选择器
# 'b'
selector.css('script::text').jmespath("a").getall()
# JMESPath 选择器
# ['b', 'c']
```