readOnly properties do not display correctly with Swagger UI in python-flask

Using this example yaml:

openapi: 3.0.0
info:
  version: 0.0.0
  title: test

paths:
  /users:
    post:
      summary: Create a user
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/User'
      responses:
        '201':
          description: Created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'

components:
  schemas:
    User:
      type: object
      properties:
        id:
          type: integer
          example: 5
          readOnly: true
        name:
          type: string
          example: Bob

I expect to see this in the request body:

{
  "name": "Bob"
}

However, I can also see the id property:

{
  "id": 5,
  "name": "Bob"
}

This occurs whenever I generate code, through both the Swagger Editor and Swagger Codegen in python-flask.

However, it displays correctly in the Swagger Editor's preview:

Swagger Editor preview is correct

I'm likely somehow generating it incorrectly, so any help would be greatly appreciated!