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LangChain

As explained in Starting Data Analytics with Generative AI and Python

LangChain is a software framework for developing applications that compose language models with prompts, tools, data sources, and conversation state.

LangChain is a Python library that simplifies connecting language models to applications. Its prebuilt functions and classes handle common API tasks, helping integrate generative AI into data-analysis workflows and dashboards. section 1.3.3

LangChain also supports local models. A typical setup uses a quantized Llama model in GGUF format with llama-cpp-python, then sends a prompt and captures the response. This minimal approach does not retain conversation memory, although LangChain can add chat memory. section 1.3.5

Calling a local Llama model

Install the LangChain and Llama libraries, create a LlamaCpp instance with the path to a GGUF model file, invoke it with a prompt, and print the response. Check current library instructions because installation requirements, especially on Windows, can change. section 1.3.5

Listing 1.5 Command to install the LangChain and Llama libraries
pip install langchain llama-cpp-python

Use the installation listing to set up LangChain with llama-cpp-python. section 1.3.5

Listing 1.6 Example of sending a prompt to Llama
from langchain_community.llms import LlamaCpp

llm = LlamaCpp(model_path='path_to_your_gguf_model_file')
response = llm.invoke('Your prompt!')
print(response)

Use the example listing to instantiate LlamaCpp, submit a prompt, and retrieve its response. section 1.3.5

How Starting Data Analytics with Generative AI and Python covers it

How deep it goes
Demonstrates installation, model invocation, and memory limitations, but defers detailed configuration to current library instructions.
Examples
Uses Python API integration, a local quantized Llama model, installation commands, and a LlamaCpp prompt invocation.
What it assumes
Assumes Python, command-line, library installation, and a downloaded model; local Llama use also requires an appropriate Meta license.
What you can do after
Apply it via Python to connect language models, send prompts, capture responses, and add conversation memory.
How it connects
Connects application programming interfaces, SDKs, prompt development, chat memory, Llama 2, GGUF, and llama-cpp-python.

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This explainer was generated by Manning's knowledge graph from the text of Starting Data Analytics with Generative AI and Python. The section links point to the parts of the book it draws on.