code: def competing_interests(soup, fntype_filter):
      
  
      competing_interests_section = extract_nodes(soup, "fn-group", attr="content-type", value="competing-interest")
      if not competing_interests_section:
          return None
      fn = extract_nodes(first(competing_interests_section), "fn")
      interests = footnotes(fn, fntype_filter)
  
      return interests
docs: Find the fn tags included in the competing interest