Run LLMs with LangChain in Google Colab
10 Feb, 2025 | 2 min read

In this blog I would like to share with you the sample code to run LLMs with LangChain in Google Colab. This setup allows you to interact with Ollama models, generate responses, and process the output seamlessly. You can explore various models, prompts, and data processing tasks using LangChain and Ollama in your Colab notebooks.

1. Install Required Modules

First, install lshw to ensure Ollama can access your system hardware, followed by the Ollama installation script.

!sudo apt-get install lshw

2. Install Ollama

Next, install Ollama using the provided script:

!curl -fsSL https://ollama.com/install.sh | sh

Then, run ollama serve in the backend, even if the above error is present. This will connect with the GPU, and ollama serve will run in the background.

import subprocess
process = subprocess.Popen(['ollama', 'serve'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
print(f"Ollama serve process ID: {process.pid}")

3. Pull Model from Ollama

There are many models available on Ollama. You can pull any model you want. Here, I am pulling the llama3.2:1b model for testing.

# Pull llama 1b parameter Model for testing
!ollama pull llama3.2:1b

4. Install LangChain

Then install LangChain in order to communicate with Ollama and process the responses.

!pip install langchain

5. Import Required Libraries

Import the necessary libraries for this task:

from langchain_core.prompts import ChatPromptTemplate
from langchain_ollama.llms import OllamaLLM
from IPython.display import display, Markdown

6. Define the Prompt

Define the prompt you want to use for generating responses:

template = """Question: {question}
Answer: Let's think step by step."""
prompt = ChatPromptTemplate.from_template(template)
model = OllamaLLM(model="llama3.2:1b")
chain = prompt | model # Chain the prompt and model

7. Generate Response

Generate a response by invoking the chain with a question and display the response in Markdown format.

result = chain.invoke({"question": "What is the capital of Cambodia?"})
display(Markdown(result))

Conclusion

You have successfully set up LangChain in Google Colab to interact with Ollama models, generate responses, and process the output.

print("Thank you for reading!")