LangChain is AMAZING | Quick Python Tutorial

LangChain is a great Python library for creating applications that communicate with Large Language Model (LLM) APIs. In this tutorial, I’ll show you how it works and also discuss its design

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👀 Code reviewers:
- Yoriz
- Ryan Laursen
- Dale Hagglund

🔖 Chapters:
0:00 Intro
0:42 LangChain Tutorial
12:23 LangChain’s design
15:58 Final Thoughts

#arjancodes #softwaredesign #python

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[NGrimthrie]

This is great. Would you consider doing a video on ways to extend the models beyond their training cutoff dates? Possibly using vector databases and LangChain's document parsers?

[pypypy]

This is a paragon of explanation: succinct and to the point, gradually increasing the difficulty, with an apt digression into principles and design patterns. I would love to see YOUR tutorials about LCEL - langchain chain expression language. I don't grasp the concept of RunnablePassthrough and nobody seems to explain it the way you explain the Python magic. ❤

[jumper]

I must have missed that survey -- I would love to see more content about databases and best-practices with them. Like using SQLAlchemy efficiently and whatnot. I do a lot of web scraping and it was only this year that I graduated from heinously large JSON files to proper databases

[dragzu]

Great video, i would really like to see how a Database Content + Model can be integrated into an LLM application (can be also GPT4all i think), so users can then ask stuff about the DB content.

[TNothingFree]

Fantastic cover.
A. it shows how complex it is, you need to understand the API correctly to make the maximum out of it.
B. I just can imagine what it can do with many products, every app/web site can integrate such automatic tools which may generate ton of content.
My favorite are infinite dungeon crawlers.

[TacticalTruth]

Looks perfect for Data Cleaning and Record Linkage.

[loietzb]

can not wait for your long-chain tutorials.

[jeffrey]

I actually enjoy the original python content the most. Especially in this AI craze I try to avoid AI content from people who weren't doing AI content before all the hype, no fence. But your great python content is what I subscribed for :)

[WirelessGus]

Hey Everyone 👋
Find the parts that interest you:

0:00 - Introduction to Lang chain and AI content
1:00 - Setting up a large language model object
3:00 - Working with templates in Lang chain
6:07 - Generating response for LM with chat prompts
7:26 - Combining Lang chain with pedantic for output formatting
10:02 - Accessing and utilizing formatted response data
12:05 - Potential applications for Lang chain
13:33 - Design patterns in Lang chain
15:59 - Importance of defining concepts in libraries

Recap by Bumpups ✏️

[torstenschindler]

Hi Arjan, what’s your take on Max Woolf’s Blog: “The Problem with Langchain” ?
Loading the environment variables via the os module is not necessary. It is done in the ChatOpenAI class anyhow.

[nuurnwui]

When this video came out, I didn’t understand it. Now I do, but to me it means Arjan wasn’t quite as good at explaining as usual. Please do more on Langchain or related technologies.

[moondevonyt]

mad props for diving deep into Langchain


however, the real game changer for me would be direct integration with modern frameworks


still, your explanations? on point


always appreciate the effort you put in, but there's always room to elevate

[aungkyawkyaw]

Do all the more on all topics please. Never stop.

[fuba]

But can you run your own models? Like can I download the llama 2 from huggingface, and query it using langchain?

[melvingeorge]

wow! this is phenomenal :) thanks, Arjan! Also, which are the books in the shelf behind you?

[adrianzuur]

One of the things about LangChain that irritates me is how when you use the ConversationChain class with memory to communicate with GPT>=3.5, it DOES NOT use the chat completion endpoint OpenAI has. Instead, it uses simple completion, formatting all of the messages in the history into a single string. I suppose this is because they want the ConversationChain to work with all sorts of LLMs, including those without a chat completion mode, but... it's not the behavior you would expect for GPT>=3.5.

[adrianobleton]

I actually have a lot of trouble following the langchain model.

For example, it's not clear to me why you use a human prompt and a system prompt in the country example. Wouldn't the system prompt alone be sufficient?

For my use cases, doing a thin wrapper around the chat gpt calls is sufficient. I do use the system prompt templates though for the initial context messages.

[frazuppi]

langchain is actually (all love to the creator)a OOP hell and not really good

[paulomtts]

Very interesting. Thanks for the video!

[default_youtube_profile]

Hello Arjan,

What keyboard are you using ?