TypeError: issubclass() arg 1 must be a class when "from langchain.schema.language_model import BaseLanguageModel"

[JinSeoung-Oh]

Checked other resources

• I added a very descriptive title to this question.
• I searched the LangChain documentation with the integrated search.
• I used the GitHub search to find a similar question and didn't find it.

Commit to Help

• I commit to help with one of those options 👆

Example Code

import os
import re
import itertools
import openai
import tiktoken
import json
from dotenv import load_dotenv

from typing import Any, Dict, List, Optional

from pydantic import Extra

from langchain.schema.language_model import BaseLanguageModel
from langchain.callbacks.manager import (
    AsyncCallbackManagerForChainRun,
    CallbackManagerForChainRun,
)
from langchain.schema import (
    AIMessage,
    HumanMessage,
    SystemMessage
)
from langchain.chains.base import Chain
from langchain.prompts.base import BasePromptTemplate
from langchain.tools import DuckDuckGoSearchRun
import langchain
from langchain.chat_models import ChatOpenAI
from langchain.tools import DuckDuckGoSearchRun
from langchain.schema import (
    AIMessage,
    HumanMessage,
    SystemMessage
)
from langchain.chains.llm import LLMChain
from langchain.prompts import PromptTemplate
from langchain.chains import SequentialChain

Description

I built Chain of Verification model.
Actually, it was running fine until yesterday
But, today, it is not working

I just �reinstalled openai version 0.28.0 to latest.
So, I changed latest to 0.28.0. But it is still not working

This is full error log

---

TypeError Traceback (most recent call last)
Cell In[3], line 13
9 from typing import Any, Dict, List, Optional
11 from pydantic import Extra
---> 13 from langchain.schema.language_model import BaseLanguageModel
14 from langchain.callbacks.manager import (
15 AsyncCallbackManagerForChainRun,
16 CallbackManagerForChainRun,
17 )
18 from langchain.schema import (
19 AIMessage,
20 HumanMessage,
21 SystemMessage
22 )

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/langchain/schema/init.py:2
1 """Schemas are the LangChain Base Classes and Interfaces."""
----> 2 from langchain_core.agents import AgentAction, AgentFinish
3 from langchain_core.caches import BaseCache
4 from langchain_core.chat_history import BaseChatMessageHistory

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/langchain_core/agents.py:37
34 from typing import Any, List, Literal, Sequence, Union
36 from langchain_core.load.serializable import Serializable
---> 37 from langchain_core.messages import (
38 AIMessage,
39 BaseMessage,
40 FunctionMessage,
41 HumanMessage,
42 )
45 class AgentAction(Serializable):
46 """A full description of an action for an ActionAgent to execute."""

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/langchain_core/messages/init.py:19
1 """Messages are objects used in prompts and chat conversations.
2
3 Class hierarchy:
(...)
15
16 """ # noqa: E501
17 from typing import Any, Dict, List, Optional, Sequence, Tuple, Union
---> 19 from langchain_core.messages.ai import AIMessage, AIMessageChunk
20 from langchain_core.messages.base import (
21 BaseMessage,
22 BaseMessageChunk,
(...)
25 messages_to_dict,
26 )
27 from langchain_core.messages.chat import ChatMessage, ChatMessageChunk

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/langchain_core/messages/ai.py:10
1 from typing import Any, List, Literal
3 from langchain_core.messages.base import (
4 BaseMessage,
5 BaseMessageChunk,
6 merge_content,
7 )
---> 10 class AIMessage(BaseMessage):
11 """Message from an AI."""
13 example: bool = False

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/pydantic/main.py:197, in pydantic.main.ModelMetaclass.new()

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/pydantic/fields.py:506, in pydantic.fields.ModelField.infer()

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/pydantic/fields.py:436, in pydantic.fields.ModelField.init()

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/pydantic/fields.py:552, in pydantic.fields.ModelField.prepare()

File ~/anaconda3/envs/torch-3.9/lib/python3.9/site-packages/pydantic/fields.py:668, in pydantic.fields.ModelField._type_analysis()

File ~/anaconda3/envs/torch-3.9/lib/python3.9/typing.py:789, in _SpecialGenericAlias.subclasscheck(self, cls)
787 return issubclass(cls.origin, self.origin)
788 if not isinstance(cls, _GenericAlias):
--> 789 return issubclass(cls, self.origin)
790 return super().subclasscheck(cls)

TypeError: issubclass() arg 1 must be a class

System Info

langchain == 0.1.11
langchain-community == 0.025
langchain-core == 0.1.30
langchain-openai == 0.0.8
langchain-text-splitters == 0.0.1

python 3.9 and linux

openai == 1.13.3

[dosubot[bot]]

Hey @JinSeoung-Oh, nice to see you back here! 😊 I remember our last interaction. I'm diving into your issue now and will get back to you with an update soon. 🛠️

[JinSeoung-Oh]

Oh, sorry..
When I installed another library, the version of RangChain changed to a different one.
I just checked it right now. I guess I need to find and install the other library.

[dosubot[bot]]

Based on the context provided, it seems like the TypeError: issubclass() arg 1 must be a class error you're encountering is a known issue that has been discussed in the LangChain repository. This error typically occurs when there's a compatibility issue between the version of langchain you're using and the dependencies it relies on.

Here are a few potential solutions that have been suggested in similar issues:

1. Install Specific Versions of Libraries: One of the solutions that received the highest positive reactions suggests installing specific versions of the libraries. You can try this by running the following commands:

   pip install pydantic==1.10.8
   pip install chromadb==0.3.26

2. Downgrade Python Version: Another solution suggests downgrading your Python version to 3.10 as there might be a compatibility issue with Python 3.11.2. You can do this using pyenv or any other Python version management tool.

3. Install Specific Versions of llama-index and langchain: Another solution with a high number of positive reactions suggests installing specific versions of llama-index and langchain that are compatible with each other:

   pip install llama-index==0.5.6
   pip install langchain==0.0.148

Please try these solutions and see if they resolve your issue. If the problem persists, it would be helpful to know more about the other libraries you recently installed that might have caused this change. This could help in identifying the exact cause of the issue.

For more details, you can refer to the following discussions and issues in the LangChain repository:

• Trouble importing langchain
• ModuleNotFoundError: No module named 'langchain.schema.document'; 'langchain.schema' is not a package
• ImportError: cannot import name 'BaseLanguageModel' from 'langchain.schema'
• TypeError: issubclass() arg 1 must be a class
• Langchain Import Issue
• Langchain Quickstart is not working for me
• Was Running Fine and now getting errors

I hope this helps! If you have any other questions or need further clarification, feel free to ask.

Sources

• Trouble importing langchain
• ModuleNotFoundError: No module named 'langchain.schema.document'; 'langchain.schema' is not a package
• mportError: cannot import name 'BaseLanguageModel' from 'langchain.schema' (/usr/local/lib/python3.10/dist-packages/langchain/schema/init.py)
• TypeError: issubclass() arg 1 must be a class
• Langchain Import Issue
• Langchain Quickstart is not working for me
• Was Running Fine and now getting errors
• libs/langchain/langchain/schema/language_model.py
• libs/langchain/pyproject.toml

About Dosu

This response is meant to be useful and save you time. It is not meant to be a precise solution, but rather a starting point for your own research.

Help me be more useful! Please leave a 👍 if this is helpful and 👎 if it is irrelevant.

If you want to continue the conversation, start your reply with @dosu-bot.

[xavier-sumba-hs]

@dosu-bot

I am getting a similar error with the newer versions of langchain

langchain                                0.2.14           
langchain-community                      0.2.2            
langchain-core                           0.2.35           
langchain-elasticsearch                  0.2.2            
langchain-openai                         0.1.22           
langchain-text-splitters                 0.2.2 
pydantic                                 2.4.1            
pydantic-core                            2.10.1 
typing-extensions                        4.12.2           
typing-inspect                           0.9.0   

I don't see a point downgrading, is there another solution?

thanks in advance