[BUG] [Python] models.set missing, when using uniqeItems: true with python-flask

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [] [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

I want to use uniqueItems: true in my spec, but the generated python-flask code won't run. It throws a ModuleNotFoundError when looking for openapi_server.models.set.Set.

Traceback (most recent call last):
  File "/usr/lib/python3.9/runpy.py", line 197, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/lib/python3.9/runpy.py", line 87, in _run_code
    exec(code, run_globals)
  File "/tmp/openapi_server/__main__.py", line 5, in <module>
    from openapi_server import encoder
  File "/tmp/openapi_server/encoder.py", line 4, in <module>
    from openapi_server.models.base_model_ import Model
  File "/tmp/openapi_server/models/__init__.py", line 6, in <module>
    from openapi_server.models.name import Name
  File "/tmp/openapi_server/models/name.py", line 9, in <module>
    from openapi_server.models.set import Set
ModuleNotFoundError: No module named 'openapi_server.models.set'

openapi-generator version

5.0.1 - based on what it says during startup

OpenAPI declaration file content or url

openapi: 3.0.1

info:
  title: yooneek
  contact:
    email: different@yooneek.com
  license:
    name: MIT
  version: 1.0.0

components:
  schemas:
    Name:
      type: object
      properties:
        id:
          type: string
        parts:
          type: array
          uniqueItems: true
          items:
            type: string

  securitySchemes:
    basic:
      type: http
      scheme: basic

paths:
  /name/{name_id}:
    summary: Operations on a name
    get:
      summary: Get an name
      operationId: get_name
      parameters:
        - name: name_id
          in: path
          description: ID of name to get
          required: true
          schema:
            type: string
      responses:
        200:
          description: successful operation
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Name'

Generation Details

Not sure what "generation details" means - unless it's how I generated the spec above? This was part of a much larger spec for which I'm trying to generate a POC service. This project has been a huge help, thanks!

Steps to reproduce

Save the above yaml to openapi.yaml and run

npx @openapitools/openapi-generator-cli generate -i openapi.yaml -g python-flask

Related issues/PRs

I couldn't find anything that seems closely related

Suggest a fix

Seems like the models.set module just isn't included? Hopefully it's a simple oversight...

Run the documented npx generation command with the provided OpenAPI YAML, then inspect the generated models/init.py and models/name.py imports alongside the missing openapi_server.models.set module. Confirm the generated python-flask project starts without ModuleNotFoundError when uniqueItems is used.