Feature: Example generation for component schemas with anyOf types

Content & configuration

Swagger/OpenAPI definition:

openapi: 3.0.2
info:
 title: Fast API
 version: 0.1.0
paths:
 /demo:
   post:
     summary: Demo
     operationId: demo_demo_post
     requestBody:
       content:
         application/json:
           schema:
             $ref: '#/components/schemas/SomeModel'
       required: true
     responses:
       '200':
         description: Successful Response
         content:
           application/json:
             schema: {}
       '422':
         description: Validation Error
         content:
           application/json:
             schema:
               $ref: '#/components/schemas/HTTPValidationError'
components:
 schemas:
   HTTPValidationError:
     title: HTTPValidationError
     type: object
     properties:
       detail:
         title: Detail
         type: array
         items:
           $ref: '#/components/schemas/ValidationError'
   SomeModel:
     title: SomeModel
     type: object
     properties:
       a:
         title: A
         anyOf:
         - type: array
           items:
             type: string
         - type: string
         default: []
       b:
         title: B
         type: array
         items:
           type: string
         default: []
   ValidationError:
     title: ValidationError
     required: [loc, msg, type]
     type: object
     properties:
       loc:
         title: Location
         type: array
         items:
           type: string
       msg:
         title: Message
         type: string
       type:
         title: Error Type
         type: string

Swagger-UI configuration options:

    const ui = SwaggerUIBundle({
       url: '/openapi.json',
   oauth2RedirectUrl: window.location.origin + '/docs/oauth2-redirect',
       dom_id: '#swagger-ui',
       presets: [
       SwaggerUIBundle.presets.apis,
       SwaggerUIBundle.SwaggerUIStandalonePreset
       ],
       layout: "BaseLayout",
       deepLinking: true
   })

Is your feature request related to a problem?

Example is not generated for component schema with anyOf types.

Describe the solution you'd like

Generate the example with the first type in the anyOf list.

Reproduce the issue in Swagger UI using the supplied OpenAPI definition and configuration, focusing on the SomeModel schema's a property. Trace the example-generation entry point to see why an anyOf schema produces no example; done means the generated example uses the first type in the anyOf list.