Flask server generation from Swagger Editor

On http://editor.swagger.io/ when trying to generate python-flask server from openapi 3 nothing happens and in the console I get the following error messages:

 

generate:1 POST https://generator3.swagger.io/api/generate 500 (Internal Server Error)
index.js:1 Uncaught (in promise) Error: Internal Server Error
at index.js:1
at tryCatch (runtime.js:62)
at Generator.invoke [as _invoke] (runtime.js:296)
at Generator.e.<computed> [as next] (runtime.js:114)
at step (asyncToGenerator.js:17)
at asyncToGenerator.js:28

 

I appear to be able to generate other types so I think this is specifically a problem with generating python-flask.

 

---------------------------------------------------------UPDATE-------------------------------------------------------------------------------------
Appears to be a problem with using 'oneOf', 'anyOf', 'allOf'. Possibly related to this issue: 

https://github.com/swagger-api/swagger-codegen/issues/9395 ?