Creating Your First Chain

Introduction

Welcome to the tutorial on creating your first chain using LangChain. This guide will walk you through the process from start to finish, providing comprehensive explanations and examples along the way.

Prerequisites

Before we begin, ensure you have the following installed on your system:

• Python 3.6 or later
• pip (Python package installer)

Step 1: Install LangChain

First, you need to install the LangChain library. Open your terminal or command prompt and run the following command:

Step 2: Set Up Your Environment

Create a new Python file, for example, my_first_chain.py. This is where you will write your code to create the chain.

Step 3: Import LangChain

In your Python file, start by importing the necessary modules from LangChain:

import langchain as lc
from langchain.chains import SimpleChain
                

Step 4: Create a Simple Chain

Next, create a simple chain that takes an input, processes it, and returns an output. Here's an example:

def process_input(input_text):
    return f"Processed: {input_text}"

simple_chain = SimpleChain(
    input_keys=["input_text"],
    output_keys=["output_text"],
    function=process_input
)
                

Step 5: Run the Chain

Now, you can run the chain with an example input. Add the following code to your file:

input_data = {"input_text": "Hello, LangChain!"}
output_data = simple_chain(input_data)
print(output_data)
                

When you run the script, you should see the processed output in your terminal:

Conclusion

Congratulations! You've created your first chain using LangChain. This basic example demonstrates how to set up and run a simple chain. From here, you can explore more advanced features and functionalities of LangChain to build more complex chains.