def _get_reference_md5sum(url):
    """By convention the md5 hash for url is stored in url + '.md5sum'."""
    url_md5sum = url + '.md5sum'
    md5sum = urllib.request.urlopen(url_md5sum).read().strip()
    return md5sum
By convention the md5 hash for url is stored in url + '.md5sum'.
detectron/utils/io.py