code: def extract_css_links(bs4):
      
  
      links = extract_links(bs4)
  
      real_css = [anchor for anchor in links if anchor.endswith(('.css', '.CSS'))]
  
      css_link_tags = [anchor['href'] for anchor in bs4.select('link[type="text/css"]')
                       if anchor.has_attr('href')]
  
      return list(set(real_css+css_link_tags))
docs: Extracting css links from BeautifulSoup object
  
      :param bs4: `BeautifulSoup`
      :return: `list` List of links