[BUG] <title>documentation example error

[jaghachi]

是否已有关于该错误的issue或讨论？ | Is there an existing issue / discussion for this?

• 我已经搜索过已有的issues和讨论 | I have searched the existing issues / discussions

该问题是否在FAQ中有解答？ | Is there an existing answer for this in FAQ?

• 我已经搜索过FAQ | I have searched FAQ

当前行为 | Current Behavior

https://qwen.readthedocs.io/en/latest/framework/Langchain.html

pydantic.errors.PydanticUserError: A non-annotated attribute was detected: top_p = 0.9. All model fields require a type annotation; if top_p is not meant to be a field, you may be able to resolve this error by annotating it as a ClassVar or updating model_config['ignored_types'].

class Qwen(LLM, ABC):
     max_token: int = 10000
     temperature: float = 0.01
     top_p = 0.9
     history_len: int = 3

期望行为 | Expected Behavior

class Qwen(LLM, ABC):
     max_token: int = 10000
     temperature: float = 0.01
     top_p: float = 0.9
     history_len: int = 3

复现方法 | Steps To Reproduce

just copy paste the example in the link.

https://qwen.readthedocs.io/en/latest/framework/Langchain.html

运行环境 | Environment

- OS:
- Python:
- Transformers:
- PyTorch:
- CUDA (`python -c 'import torch; print(torch.version.cuda)'`):

备注 | Anything else?

No response