text: 
  from bs4 import BeautifulSoup
  import re
  
  
  html_doc = """
  <html><head><title>The Dormouse's story</title></head>
  <body>
  <p class="title"><b>The Dormouse's story</b></p>
  
  <p class="story">Once upon a time there were three little sisters; and their names were
  <a href="http://example.com/elsie" class="sister" id="link1">Elsie</a>,
  <a href="http://example.com/lacie" class="sister" id="link2">Lacie</a> and
  <a href="http://example.com/tillie" class="sister" id="link3">Tillie</a>;
  and they lived at the bottom of a well.</p>
  
  <p class="story">...</p>
  """
  
  
  soup = BeautifulSoup(html_doc,'html.parser',from_encoding='utf8')
  
  # 查找所有标签为a的节点
  links = soup.find_all('a')
  
  for  link in links:
      print(link.name,link['href'],link.get_text())
  
  
  # 查找所有标签为a 链接符合http://example.com/lacie形式的节点
  link_node = soup.find('a',href='http://example.com/lacie')
  print(link_node.name,link_node['href'],link_node.get_text())
  
  
  # 正则表达式匹配
  link_nodes = soup.find_all('a',href=re.compile(r'ill'))
  for  link in link_nodes:
      print(link.name,link['href'],link.get_text())
  
  
  #查找所有标签为div class 为abc 文字为python的节点
  link_classnodes = soup.find_all('p',class_='story',text='...')
  
  for  link in link_classnodes:
      print(link.name,link.get_text())
  
  
  