pydev debugger: starting (pid: 7212)craw 1,http://baike.baidu.com/item/PythonTraceback (most recent call last):? File "D:\eclipse-standard_downza\eclipse\plugins\org.python.pydev_3.9.0.201411111611\pysrc\pydevd.py", line 2183, in <module>? ? globals = debugger.run(setup['file'], None, None)? File "D:\eclipse-standard_downza\eclipse\plugins\org.python.pydev_3.9.0.201411111611\pysrc\pydevd.py", line 1622, in run? ? pydev_imports.execfile(file, globals, locals) ?# execute the script? File "D:\workspase\imooc\baike_spider\spider_main.py", line 41, in <module>? ? obj_spider.craw(root_url)? File "D:\workspase\imooc\baike_spider\spider_main.py", line 25, in craw? ? new_urls,new_data=self.parser.parse(new_url,html_cont)? File "D:\workspase\imooc\baike_spider\html_parser.py", line 35, in parse? ? soup = BeautifulSoup(html_cont,'html_parser',from_encoding='utf-8')? File "C:\Python27\lib\site-packages\bs4\__init__.py", line 165, in __init__? ? % ",".join(features))bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: html_parser. Do you need to install a parser library?