Generates invalid python code for seemingly correct json

使用提供的 OpenAPI 片段搭配 openapi-python-client 0.28.3 重現問題，然後追蹤 nullable 基本型別 schema 的 request-body 產生流程。payload 未指定任何儲存庫檔案或測試；完成條件是產生的 endpoint 模組在語法上有效，並且能處理基本型別 request body，而不會出現報告中所示的孤立 else。

Describe the bug
generator around primitives in request body fails
OpenAPI Spec File
I cannot share the full spec but this is an excempt:

    "/api/helloworlduser/{externalId}/something": {
      "patch": {
        "tags": [
          "UpdateHelloWorldUser"
        ],
        "description": "Update user",
        "operationId": "HelloWorldUserUpdate",
        "parameters": [
          {
            "name": "externalId",
            "in": "path",
            "required": true,
            "schema": {
              "type": "string"
            }
          }
        ],
        "requestBody": {
          "content": {
            "application/json": {
              "schema": {
                "type": "number",
                "format": "double",
                "nullable": true
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "OK",
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/UserReadDTO"
                }
              }
            }
          }
        }
      }
    },

this generates the file:

from http import HTTPStatus
from typing import Any, cast
from urllib.parse import quote

import httpx

from ...client import AuthenticatedClient, Client
from ...types import Response, UNSET
from ... import errors

from ...models.user_read_dto import UserReadDTO
from ...types import UNSET, Unset
from typing import cast



def _get_kwargs(
    external_id: str,
    *,
    body: float | None | Unset = UNSET,

) -> dict[str, Any]:
    headers: dict[str, Any] = {}


    

    

    _kwargs: dict[str, Any] = {
        "method": "patch",
        "url": "/api/helloworlduser/{external_id}/something".format(external_id=quote(str(external_id), safe=""),),
    }

    
    else:
        _kwargs["json"] = body


    headers["Content-Type"] = "application/json"

    _kwargs["headers"] = headers
    return _kwargs



def _parse_response(*, client: AuthenticatedClient | Client, response: httpx.Response) -> UserReadDTO | None:
    if response.status_code == 200:
        response_200 = UserReadDTO.from_dict(response.json())



        return response_200

    if client.raise_on_unexpected_status:
        raise errors.UnexpectedStatus(response.status_code, response.content)
    else:
        return None


def _build_response(*, client: AuthenticatedClient | Client, response: httpx.Response) -> Response[UserReadDTO]:
    return Response(
        status_code=HTTPStatus(response.status_code),
        content=response.content,
        headers=response.headers,
        parsed=_parse_response(client=client, response=response),
    )


def sync_detailed(
    external_id: str,
    *,
    client: AuthenticatedClient | Client,
    body: float | None | Unset = UNSET,

) -> Response[UserReadDTO]:
    """  Update user

    Args:
        external_id (str):
        body (float | None | Unset):

    Raises:
        errors.UnexpectedStatus: If the server returns an undocumented status code and Client.raise_on_unexpected_status is True.
        httpx.TimeoutException: If the request takes longer than Client.timeout.

    Returns:
        Response[UserReadDTO]
     """


    kwargs = _get_kwargs(
        external_id=external_id,
body=body,

    )

    response = client.get_httpx_client().request(
        **kwargs,
    )

    return _build_response(client=client, response=response)

def sync(
    external_id: str,
    *,
    client: AuthenticatedClient | Client,
    body: float | None | Unset = UNSET,

) -> UserReadDTO | None:
    """  Update user

    Args:
        external_id (str):
        body (float | None | Unset):

    Raises:
        errors.UnexpectedStatus: If the server returns an undocumented status code and Client.raise_on_unexpected_status is True.
        httpx.TimeoutException: If the request takes longer than Client.timeout.

    Returns:
        UserReadDTO
     """


    return sync_detailed(
        external_id=external_id,
client=client,
body=body,

    ).parsed

async def asyncio_detailed(
    external_id: str,
    *,
    client: AuthenticatedClient | Client,
    body: float | None | Unset = UNSET,

) -> Response[UserReadDTO]:
    """  Update user

    Args:
        external_id (str):
        body (float | None | Unset):

    Raises:
        errors.UnexpectedStatus: If the server returns an undocumented status code and Client.raise_on_unexpected_status is True.
        httpx.TimeoutException: If the request takes longer than Client.timeout.

    Returns:
        Response[UserReadDTO]
     """


    kwargs = _get_kwargs(
        external_id=external_id,
body=body,

    )

    response = await client.get_async_httpx_client().request(
        **kwargs
    )

    return _build_response(client=client, response=response)

async def asyncio(
    external_id: str,
    *,
    client: AuthenticatedClient | Client,
    body: float | None | Unset = UNSET,

) -> UserReadDTO | None:
    """  Update user

    Args:
        external_id (str):
        body (float | None | Unset):

    Raises:
        errors.UnexpectedStatus: If the server returns an undocumented status code and Client.raise_on_unexpected_status is True.
        httpx.TimeoutException: If the request takes longer than Client.timeout.

    Returns:
        UserReadDTO
     """


    return (await asyncio_detailed(
        external_id=external_id,
client=client,
body=body,

    )).parsed

which is a complete broken file (see the else in get_kwargs).

Desktop (please complete the following information):

• OS: mac os
• Python Version: 3.14
• openapi-python-client version: 0.28.3