OpenAI instance of Runnable expected

[wonderkidshihab]

System Info

Hi there,

I have started learning about Langchain today. I was creating my first langchain prompt template but something doesn't seem to work.

Here is my code in main.py:

from openai import OpenAI
from dotenv import load_dotenv
from langchain.prompts import PromptTemplate
from langchain.chains import LLMChain
import os

# Load the .env file
load_dotenv()

# Create an instance of the OpenAI class
def generate_pet_name(animal_type="dog"):
    
    prompt_template = PromptTemplate(
        input_variables=['animal_type'],
        template="I have a {animal_type} as my pet. Suggest me a name for it.",
    )

    name_chain = LLMChain(
        llm=OpenAI(),
        prompt=prompt_template,
    )

    response = name_chain({'animal_type': animal_type})
    print(response)


if __name__ == "__main__":
    generate_pet_name(animal_type="dog")

While I think the code is okay and I have followed the GitHub get started it doesn't seem to work and throwing me this error:

Traceback (most recent call last):
  File "/Users/ss/Workspace/Ai/AMP/main.py", line 28, in <module>
    generate_pet_name(animal_type="dog")
  File "/Users/ss/Workspace/Ai/AMP/main.py", line 18, in generate_pet_name
    name_chain = LLMChain(
                 ^^^^^^^^^
  File "/Users/ss/Workspace/Ai/AMP/.venv/lib/python3.11/site-packages/langchain/load/serializable.py", line 97, in __init__
    super().__init__(**kwargs)
  File "/Users/ss/Workspace/Ai/AMP/.venv/lib/python3.11/site-packages/pydantic/v1/main.py", line 341, in __init__
    raise validation_error
pydantic.v1.error_wrappers.ValidationError: 2 validation errors for LLMChain
llm
  instance of Runnable expected (type=type_error.arbitrary_type; expected_arbitrary_type=Runnable)
llm
  instance of Runnable expected (type=type_error.arbitrary_type; expected_arbitrary_type=Runnable)

Please Help me as I am not that proficient in Python.

Who can help?

@agola11

Information

• The official example notebooks/scripts
• My own modified scripts

Related Components

• LLMs/Chat Models
• Embedding Models
• Prompts / Prompt Templates / Prompt Selectors
• Output Parsers
• Document Loaders
• Vector Stores / Retrievers
• Memory
• Agents / Agent Executors
• Tools / Toolkits
• Chains
• Callbacks/Tracing
• Async

Reproduction

Just copy the code given there and run it. You will see the error.

Expected behavior

Run the code and get a response without error

[dosubot]

🤖

Hello @wonderkidshihab,

I'm Dosu, a friendly bot here to assist you in navigating the LangChain repository. I can help you solve bugs, answer your questions, and guide you on your journey to becoming a contributor. While we're waiting for a human maintainer, I'm here to help.

I'm currently reviewing your issue and will provide a more complete response shortly. Thank you for your patience.

[dosubot]

🤖

It seems like the error you're encountering is due to the OpenAI() instance not being a Runnable type, which is expected by the LLMChain class.

In LangChain, a Runnable is a class that wraps a function or generator function and provides methods for invoking it synchronously or asynchronously. There are several types of Runnable classes provided by the framework, including RunnableLambda, RunnableGenerator, RunnableParallel, RunnableSequence, RunnableMap, and RunnableBinding.

The LLMChain class in LangChain is used as a component for running queries against Language Models (LLMs) and generating language model results from inputs. It expects an instance of a Runnable class but it seems like it's receiving something else in your case.

A similar issue was encountered and solved in the LangChain repository. The solution was to create a wrapper class for the language model that inherits from BaseLanguageModel and implements the required methods. Here's how you could do it:

from langchain.schema.language_model import BaseLanguageModel
from openai import OpenAI

class OpenAIWrapper(BaseLanguageModel):
    def __init__(self):
        self.llm = OpenAI()

    def generate(self, prompts, **kwargs):
        # Implement the generate method using self.llm
        pass

    # Implement other required methods...

Then, you can use this wrapper class when creating an instance of LLMChain:

llm = OpenAIWrapper()
name_chain = LLMChain(
    llm=llm,
    prompt=prompt_template,
)

Please note that you'll need to implement the generate method and any other methods required by BaseLanguageModel in the OpenAIWrapper class. The implementation of these methods should use the OpenAI instance stored in self.llm.

You can refer to the Issue with Langchain LLM Chains for more details.

I hope this helps! If you have any other questions or if something is unclear, feel free to ask.

Sources

• Issue with Langchain LLM Chains
• libs/langchain/langchain/schema/runnable/base.py
• libs/langchain/langchain/chains/base.py
• libs/langchain/tests/unit_tests/schema/snapshots/test_runnable.ambr
• libs/langchain/langchain/chains/llm.py
• libs/langchain/langchain/chains/llm_math/base.py
• libs/langchain/langchain/chains/llm_checker/base.py

---

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.

[adfriend2003]

I faced this issue and the resolution is following:

The issue is this line:
from openai import OpenAI

Replace above line with following:
from langchain.llms import OpenAI

Hence, the prob is wrong package.

[wonderkidshihab]

@adfriend2003 Thanks man... it helped me a lot

[Zeeshan0123]

import os
os.environ["GOOGLE_API_KEY"] = ''

from langchain.prompts import PromptTemplate

post_prompt = PromptTemplate.from_template(
"""You are a business owner. Given the theme of a post, write a social media post to share on my socials.

Theme: {theme}
Content: This is social media post based on the theme above:"""
)

review_prompt = PromptTemplate.from_template(
"""You are an expert social media manager. Given the presented social media post, it is your job to write a review for the post.

Social Media Post:
{post}
Review from a Social Media Expert:"""
)

from llama_index.llms.palm import PaLM

llm = PaLM(temperature=5)

from langchain_core.runnables import RunnablePassthrough
chain = (
{"post": RunnablePassthrough() | post_prompt | llm | output_parser }
| review_prompt
| llm
| output_parser
)

chain.invoke({"theme": "Having a black friday sale with 50% off on everything."})

---

TypeError Traceback (most recent call last)
in <cell line: 3>()
1 from langchain_core.runnables import RunnablePassthrough
2 chain = (
----> 3 {"post": RunnablePassthrough() | post_prompt | llm | output_parser }
4 | review_prompt
5 | llm

TypeError: Expected a Runnable, callable or dict.Instead got an unsupported type: <class 'llama_index.llms.palm.PaLM'>

anyone resolve this error please share the solution

[bretzNiklas]

For me this issue was caused by importing a function named "llm" that shadowed the actual llm variable i wanted to use.
I fixed this by going from
import llm

to

from llm import llm

[l024258]

I faced this issue and the resolution is following:

The issue is this line: from openai import OpenAI

Replace above line with following: from langchain.llms import OpenAI

Hence, the prob is wrong package.

I am facing the similar problem with

from langchain_openai import AzureChatOpenAI, AzureOpenAI
langchain version is 0.1.4

Can someone help me out here?