def check_fulltext(record):
    """
    Checks several fields and returns True, if there is probably a link to fulltext.
    """
    try:
        type = record['024']['2']
    except:
        type = ''
    try:
        urls = record.get_fields('856')
    except:
        urls = ''
    for url in urls:
        description = url.get_subfields('3')
        if (not description or 'kostenfrei' in description or 
            'Digitalisierung' in description or 'zugänglich' in description):
            has_fulltext_url = True
            break
    else:
        has_fulltext_url = False
    if urls and has_fulltext_url or urls and (format == 'doi' or format ==
        'urn'):
        return True
    else:
        return False
