Downloadable openapi.json

[teddybee]

Is your feature request related to a problem? Please describe.
For api class generators, it would be good to have an openapi.json. Unfortunately I cannot figure out how can I download that from the docs page.

Describe the solution you'd like
A link to docs page or an api url that serve that file.

P.S.: like this
https://petstore3.swagger.io/api/v3/openapi.json