python 报错 bs4 FeatureNotFound: Couldn‘t find a tree builder with the features you requested: lxml

￡神魔★判官ぃ 2021-09-07 06:01 222阅读 0赞

安装beautifulsoup后，运行测试报错

from urllib import request
    from bs4 import BeautifulSoup
    
    url = "http://www.baidu.com"
    rsp = request.urlopen(url)
    content = rsp.read()
    
    soup = BeautifulSoup(content, "lxml")
    
    print(soup.title.string)

运行结果：

----------------------------------------------------------------------
    FeatureNotFound                      Traceback (most recent call last)
    ~/data/spider/bs.py in <module>
         16 content = rsp.read()
         17 
    ---> 18 soup = BeautifulSoup(content, "lxml")
         19 
         20 print(soup.title.string)
    
    ~/data/spider/venv/lib/python3.7/site-packages/bs4/__init__.py in __init__(self, markup, features, builder, parse_only, from_encoding, exclude_encodings, **kwargs)
        196                     "Couldn't find a tree builder with the features you "
        197                     "requested: %s. Do you need to install a parser library?"
    --> 198                     % ",".join(features))
        199             builder = builder_class()
        200             if not (original_features == builder.NAME or
    
    FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

经过测试发现是lxml的问题，使用 pip install lxml 安装，安装完后，在运行还是一样出错, 经百度、知乎的说法是新的库不支持，新版本语法支持改变了

使用 pip install lxml时，自动安装的是最新 4.2.5版本

解决方法一:

卸载新的换老的就可以了

pip uninstall lxml

pip install lxml==3.7.0

方法二：

在报错代码中把函数参数中所有的 "lxml" 改成 "html.parser"

soup = BeautifulSoup(content, "lxml")

改成

soup = BeautifulSoup(content, "html.parser")