title: AttributeError: 'ResultSet' object has no attribute 'find_all'
body: <p>Where is error? I want to parse my text without tags.</p>
  
  <pre><code>from bs4 import BeautifulSoup       
  import re
  import urllib.request
  f = urllib.request.urlopen("http://www.championat.com/football/news-2442480-orlov-zenit-obespokoen---pole-na-novom-stadione-mozhet-byt-nekachestvennym.html")
  
  soup = BeautifulSoup(f, 'html.parser')
  
  soup=soup.find_all('div', class_="text-decor article__contain")
  
  invalid_tags = ['b', 'i', 'u', 'br', 'a']
  
  for tag in invalid_tags: 
  
    for match in soup.find_all(tag):
  
          match.replaceWithChildren()
  
  soup = ''.join(map(str, soup.contents))
  
  print (soup)
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "1.py", line 9, in &lt;module&gt;
      for match in soup.find_all(tag):
  AttributeError: 'ResultSet' object has no attribute 'find_all'
  </code></pre>