Connexion is a framework that automagically handles HTTP requests based on OpenAPI Specification (formerly known as Swagger Spec) of your API described in YAML format. Connexion allows you to write an OpenAPI specification, then maps the endpoints to your Python functions; this makes it unique, as many tools generate the specification based on your Python code. You can describe your REST API in as much detail as you want; then Connexion guarantees that it will work as you specified.
Thank you Zalando for sharing this code.