问AuthFailure 4100 ，用的官方的python例子，求原因？

def get_string_to_sign(method, endpoint, params):
    s = method + endpoint + "/?"
    query_str = "&".join("%s=%s" % (k, data[k]) for k in sorted(data))
    return s + query_str

def sign_str(key, s, method):
    hmac_str = hmac.new(key.encode("utf8"), s.encode("utf8"), method).digest()
    return base64.b64encode(hmac_str)

if __name__ == '__main__':
    endpoint = "vod.api.qcloud.com/v2/index.php"
    data = {
        'Action': 'GetVideoInfo',
        'fileId': '5285890781569505487',
        'infoFilter.0': 'basicInfo',
        'Nonce': 5252,
        'Region': 'sh',
        'SecretId': secretId,
        'Timestamp': int(time.time())
    }
    s = get_string_to_sign("GET", endpoint, data)
    data["Signature"] = sign_str(secretKey, s, hashlib.sha1)

    print(data["Signature"])
    resp = requests.get("https://" + endpoint, params=data)
    print(resp.url)