Generates invalid python code for seemingly correct json

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

Tái hiện vấn đề bằng đoạn trích OpenAPI được cung cấp với openapi-python-client 0.28.3, sau đó lần theo quá trình tạo request-body cho các schema nguyên thủy nullable. Payload không nêu tên tệp nào trong repository hay test nào; công việc được hoàn tất khi module endpoint được tạo ra hợp lệ về cú pháp và xử lý request body nguyên thủy mà không có else mồ côi được nêu trong báo cáo.