def _is_parsing_required(torrent):
    """Determines if parsing is required.

    Checks the following attributes to determine if parsing is needed:
    - if torrent.invalid is True, skip parsing
    - if torrent.purged is True, skip parsing
    - if len(torrent.media_files) > 0, skip parsing
    """
    parse = True
    if torrent.invalid:
        parse = False
    if torrent.purged:
        parse = False
    if torrent.media_files:
        parse = False
    return parse
