Bug: GraphIndexCreator raises PydanticUserError when instantiated; NetworkX tutorial notebook not running.

[MrVaibhavChamp]

Checked other resources

• I added a very descriptive title to this issue.
• I searched the LangChain documentation with the integrated search.
• I used the GitHub search to find a similar question and didn't find it.
• I am sure that this is a bug in LangChain rather than my code.
• The bug is not resolved by updating to the latest stable version of LangChain (or the specific integration package).

Example Code

Run the following code:

from langchain_community.graphs.index_creator import GraphIndexCreator
from langchain_openai import OpenAI
index_creator = GraphIndexCreator(llm=OpenAI(temperature=0, api_key=OPENAI_API_KEY))

Remember to use your own OpenAI API key.

Error Message and Stack Trace (if applicable)

PydanticUserError Traceback (most recent call last)
in <cell line: 1>()
----> 1 index_creator = GraphIndexCreator(llm=OpenAI(temperature=0, api_key=OPENAI_API_KEY)) [... skipping hidden 1 frame]

/usr/local/lib/python3.10/dist-packages/pydantic/_internal/_mock_val_ser.py in getattr(self, item)
98 # raise an AttributeError if item doesn't exist
99 getattr(self._val_or_ser, item)
--> 100 raise PydanticUserError(self._error_message, code=self._code)
101
102 def rebuild(self) -> ValSer | None:

PydanticUserError: GraphIndexCreator is not fully defined; you should define BaseCache, then call GraphIndexCreator.model_rebuild().

Description

Was trying to run the following networkx tutorial: https://github.com/langchain-ai/langchain/blob/master/docs/docs/integrations/graphs/networkx.ipynb.

I encountered a PydanticUserError when attempting to instantiate the GraphIndexCreator. It seems that BaseCache needs to be defined and GraphIndexCreator.model_rebuild() must be called, but this isn't mentioned in the documentation or examples.

System Info

This was run in the usual Google Colab environment.