How to install LangChain in python

Setup

pip install langchain

from langchain_openai import ChatOpenAI, OpenAIEmbeddings
from langchain_community.vectorstores import FAISS
from langchain_community.document_loaders import TextLoader
from langchain_core.prompts import ChatPromptTemplate

Examples

Integration steps

1. Run the command pip install langchain in your terminal to install the package.
2. Import LangChain modules from langchain_openai and langchain_community as needed.
3. Initialize LangChain clients or loaders in your Python code.
4. Use LangChain classes and methods to build your AI application.
5. Run your Python script to verify LangChain is installed and working.

Full code

from langchain_openai import ChatOpenAI, OpenAIEmbeddings
from langchain_community.vectorstores import FAISS
from langchain_community.document_loaders import TextLoader
from langchain_core.prompts import ChatPromptTemplate

# Example: Initialize a ChatOpenAI client
client = ChatOpenAI(model_name='gpt-4o')
print(f"LangChain client initialized with model: {client.model_name}")

LangChain client initialized with model: gpt-4o

API trace

N/A - installation and import do not send API requests

N/A - installation and import do not receive API responses

Variants

pip install langchain[openai,faiss]

pip install langchain[gpu]

python -m venv env
source env/bin/activate
pip install langchain

Performance

• Use concise prompts to reduce token usage.
• Cache embeddings or vector store results to avoid repeated calls.
• Batch requests when possible to optimize throughput.