docs: def extract_links(bs4):
      """Extracting links from BeautifulSoup object
  
      :param bs4: `BeautifulSoup`
      :return: `list` List of links
      """
  
      unique_links = list(set([anchor['href'] for anchor in bs4.select('a[href]') if anchor.has_attr('href')]))
  
      # remove irrelevant link
      unique_links = [link for link in unique_links if link != '#']
  
      # convert invalid link with adding 'http' schema
      return [convert_invalid_url(link) for link in unique_links]