Amazon API Gateway Supports API Definition Import and Export
aws.amazon.com/about-aws/whats-new/2015/12/amazon-api-gateway-supports-api-definition-import-and-export
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
You can now export API definitions for Amazon API Gateway. Through a new API you can export your API configurations as a Swagger file from the API Gateway Management Console. You can export Swagger definitions including the API Gateway integration tags as well as POSTMAN annotations. Read our documentation to learn more about this feature.