<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def rel_links(cls, page):
 """return rel= links that should be scraped, skipping obviously data links."""

    for match in cls.REL_RE.finditer(page):
      href, rel = match.group(0), match.group(1)
      if rel not in cls.REL_TYPES:
        continue
      href_match = cls.HREF_RE.search(href)
      if href_match:
        href = cls.href_match_to_url(href_match)
        parsed_href = urlparse(href)
        if any(parsed_href.path.endswith(ext) for ext in cls.REL_SKIP_EXTENSIONS):
          continue
        yield href