def METHOD_NAME(fullname, md5sum=None):
    if md5sum is None:
        return True
    md5 = hashlib.md5()
    with open(fullname, 'rb') as f:
        for chunk in iter(lambda: f.read(4096), b""):
            md5.update(chunk)
    calc_md5sum = md5.hexdigest()
    if calc_md5sum != md5sum:
        return False
    return True