用的是deepseek模型。deepsek的链接密钥这些确定没有问题，都试过了。
Client端输入问题后，返回如下错误：
Simplified request error: Connection error.
Error: cannot access local variable 'completion' where it is not associated with a value

能够基础判断是以下这段发生的：
completion = await self.openai.chat.completions.create(
model=os.getenv("OPENAI_MODEL"),
max_tokens=1000,
messages=messages,
tools=available_tools
)

代理问题，这个不清楚，但是设置代理后 启动服务就报错。

• Exception Group Traceback (most recent call last):
  | File "C:\Workbooks\ple\mcp_client\client.py", line 289, in main
  | await client.connect_to_sse_server(server_url=sys.argv[1])
  | File "C:\Workbooks\ple\mcp_client\client.py", line 159, in connect_to_sse_server
  | streams = await self._streams_context.aenter()
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  | File "C:\Users\user\AppData\Local\Programs\Python\Python313\Lib\contextlib.py", line 214, in aenter
  | return await anext(self.gen)
  | ^^^^^^^^^^^^^^^^^^^^^
  | File "C:\Workbooks\ple\mcp_client.venv\Lib\site-packages\mcp\client\sse.py", line 43, in sse_client
  | async with anyio.create_task_group() as tg:
  | ~~~~~~~~~~~~~~~~~~~~~~~^^
  | File "C:\Workbooks\ple\mcp_client.venv\Lib\site-packages\anyio_backends_asyncio.py", line 772, in aexit
  | raise BaseExceptionGroup(
  | "unhandled errors in a TaskGroup", self._exceptions
  | ) from None
  | ExceptionGroup: unhandled errors in a TaskGroup (1 sub-exception)
  +-+---------------- 1 ----------------
  | Traceback (most recent call last):
  | File "C:\Workbooks\ple\mcp_client.venv\Lib\site-packages\mcp\client\sse.py", line 53, in sse_client
  | event_source.response.raise_for_status()
  | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  | File "C:\Workbooks\ple\mcp_client.venv\Lib\site-packages\httpx_models.py", line 829, in raise_for_status
  | raise HTTPStatusError(message, request=request, response=self)
  | httpx.HTTPStatusError: Client error '403 Target service not allowed' for url 'http://111.139.23:8020/sse'
  | For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/403
  +------------------------------------

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "C:\Workbooks\ple\mcp_client\client.py", line 297, in
asyncio.run(main())
~~~~~~~~~~~^^^^^^^^
File "C:\Users\user\AppData\Local\Programs\Python\Python313\Lib\asyncio\runners.py", line 194, in run
return runner.run(main)
~~~~~~~~~~^^^^^^
File "C:\Users\user\AppData\Local\Programs\Python\Python313\Lib\asyncio\runners.py", line 118, in run
return self._loop.run_until_complete(task)
File "C:\Users\user\AppData\Local\Programs\Python\Python313\Lib\asyncio\base_events.py", line 720, in run_until_complete
return future.result()
~~~~~~~~~~~~~^^
File "C:\Workbooks\ple\mcp_client\client.py", line 292, in main
await client.cleanup()
File "C:\Workbooks\ple\mcp_client\client.py", line 176, in cleanup
if self._session_context:
^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'MCPClient' object has no attribute '_session_context'