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title: "Importing Hub Fails with Latest LangChain Version 0.3.9" tags: - langchain - hub - import error

Core Problem

The latest version of LangChain, specifically 0.3.9, causes an issue when trying to import the hub module.

Solution & Analysis

Step 1: Check for deprecated imports

Due to a deprecation notice in Pydantic, the original code importing the hub module will not work with the latest version of LangChain. To fix this, we need to update our imports using the recommended @model_validator decorator instead of the deprecated @root_validator.

Step 2: Update the import

from langchain.agents.agent import Agent
from langchain.chains.conversation.base import ConversationChain
from langchain.prompts.prompt import PromptTemplate
from langchain.prompts.base import BasePromptTemplate

Conclusion

In conclusion, upgrading to the latest version of LangChain (0.3.9) results in an ImportError due to a Pydantic deprecation issue. By updating our imports to use the recommended @model_validator decorator, we can resolve this issue and continue using the hub module for pulling prompts.

Reference