下面是php的程式碼，轉換成python程式碼

<?php

// Your Access Key ID, as taken from the Your Account page
$access_key_id = "";

// Your Secret Key corresponding to the above ID, as taken from the Your Account page
$secret_key = "";

// The region you are interested in
$endpoint = "webservices.amazon.com";

$uri = "/onca/xml"
 
;

$params = array(
    "Service" => "AWSECommerceService",
    "Operation" => "undefined",
    "AWSAccessKeyId" => "",
    "AssociateTag" => ""
);

// Set current timestamp if not set
if (!isset($params["Timestamp"])) {
    $params["Timestamp"] = gmdate('Y-m-d\TH:i:s\Z');
}

// Sort the parameters by key
 

ksort($params);

$pairs = array();

foreach ($params as $key => $value) {
    array_push($pairs, rawurlencode($key)."=".rawurlencode($value));
}

// Generate the canonical query
$canonical_query_string = join("&", $pairs);

// Generate the string to be signed
$string_to_sign = "GET\n".$endpoint."\n"
 
.$uri."\n".$canonical_query_string;

// Generate the signature required by the Product Advertising API
$signature = base64_encode(hash_hmac("sha256", $string_to_sign, $secret_key, true));

// Generate the signed URL
$request_url = 'https://'.$endpoint.$uri.'?'.$canonical_query_string.'&Signature='.rawurlencode($signature);

echo "Signed URL: \"".$request_url."\"";

?>

python 生成簽名

secretAccessKey = ""
AssociateTag = ""
AWSAccessKeyId = ""
base_url = "https://webservices.amazon.com/onca/xml"

url_params = {
    "Service": "AWSECommerceService",
    "Operation": "ItemSearch",
    "AWSAccessKeyId": AWSAccessKeyId,
    "AssociateTag": AssociateTag,
    "SearchIndex": searchIndex,
    "Keywords": keywords,
    "ResponseGroup": "Images,ItemAttributes,Offers",
    "Timestamp": time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime())
}
# 將引數排序
keys = url_params.keys()
keys.sort()
array = []
# 拼接引數：
for k in keys:
    array.append(urllib.quote(k) + '=' + urllib.quote(url_params.get(k)))
url_string = '&'.join(array)
# 生成簽名
string_to_sign = "GET\n" + "webservices.amazon.com\n" + "/onca/xml\n%s" % url_string
signature = hmac.new(key=secretAccessKey, msg=string_to_sign, digestmod=hashlib.sha256).digest()
signature = urllib.quote(base64.b64encode(signature))

url_string += "&Signature=%s" % signature
request_url = "%s?%s" % (base_url, url_string)

注：
1、引數要排序
2、生成簽名的string_to_sign的語句，必須用\n 不能使用”’ ”’
3、生成簽名用sha256，用base64解壓
4、再urllib.quote 生成url