Amazon Pay API-如何获取AWSAccessKeyId和签名

Question

我在Alexa Skill中使用Amazon Pay付款。我正在进行Amazon Pay API集成以启动退款。

这是Amazon Pay上记录的示例API请求

POST /OffAmazonPayments/2013-01-01 HTTP/1.1
Content-Type: x-www-form-urlencoded
Host: mws.amazonservices.com1
User-Agent:

  AWSAccessKeyId=AKIAFBM3LG5JEEXAMPLE
  &Action=Refund
  &AmazonCaptureId=P01-1234567-1234567-0000002
  &RefundAmount.Amount=94.50
  &RefundAmount.CurrencyCode=USD
  &RefundReferenceId=test_refund_1
  &SellerRefundNote=Lorem%20ipsum
  &SellerId=YOUR_SELLER_ID_HERE
  &SignatureMethod=HmacSHA256
  &SignatureVersion=2
  &Timestamp=2012-11-05T19%3A01%3A11Z
  &Version=2013-01-01
  &Signature=WlQ708aqyHXMkoUBk69Hjxj8qdh3aDcqpY71hVgEXAMPLE

我不确定如何获取所需的AWSAccessKeyId和签名来执行此API。

任何人都可以帮我在哪里找到它。