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+{
+ "cells": [
+ {
+ "cell_type": "markdown",
+ "id": "dfe37963-1af6-44fc-a841-8e462443f5e6",
+ "metadata": {},
+ "source": [
+ "## Expert Knowledge Worker\n",
+ "\n",
+ "### A question answering agent that is an expert knowledge worker\n",
+ "### To be used by employees of Insurellm, an Insurance Tech company\n",
+ "### The agent needs to be accurate and the solution should be low cost.\n",
+ "\n",
+ "This project will use RAG (Retrieval Augmented Generation) to ensure our question/answering assistant has high accuracy."
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 1,
+ "id": "ba2779af-84ef-4227-9e9e-6eaf0df87e77",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# imports\n",
+ "\n",
+ "import os\n",
+ "import glob\n",
+ "from dotenv import load_dotenv\n",
+ "import gradio as gr"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 7,
+ "id": "78743444-cae7-4fad-bf66-dcfabbe73335",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "!pip install -U -q imapclient langchain langchain-openai langchain-chroma langchain-community langchain-core langchain-text-splitters langchain-huggingface chromadb sentence-transformers"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 27,
+ "id": "802137aa-8a74-45e0-a487-d1974927d7ca",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# # imports for langchain\n",
+ "\n",
+ "# from langchain.document_loaders import DirectoryLoader, TextLoader\n",
+ "# from langchain.text_splitter import CharacterTextSplitter\n",
+ "# from langchain.schema import Document\n",
+ "# from langchain_openai import OpenAIEmbeddings, ChatOpenAI\n",
+ "# from langchain_chroma import Chroma\n",
+ "# import numpy as np\n",
+ "# from sklearn.manifold import TSNE\n",
+ "# import plotly.graph_objects as go\n",
+ "# from langchain.memory import ConversationBufferMemory\n",
+ "# from langchain.chains import ConversationalRetrievalChain"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 3,
+ "id": "e0e47493-d020-4fe4-bac9-6dc42dee1841",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# # imports for langchain\n",
+ "\n",
+ "# imports for langchain (modular setup)\n",
+ "from langchain_core.documents import Document\n",
+ "from langchain_core.messages import HumanMessage\n",
+ "from langchain_text_splitters import CharacterTextSplitter\n",
+ "from langchain_openai import OpenAIEmbeddings, ChatOpenAI\n",
+ "from langchain_chroma import Chroma\n",
+ "from langchain_huggingface import HuggingFaceEmbeddings\n",
+ "from langchain_core.callbacks import StdOutCallbackHandler\n",
+ "# Other imports\n",
+ "import numpy as np\n",
+ "from sklearn.manifold import TSNE\n",
+ "import plotly.graph_objects as go\n"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 4,
+ "id": "58c85082-e417-4708-9efe-81a5d55d1424",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# price is a factor for our company, so we're going to use a low cost model\n",
+ "\n",
+ "MODEL = \"gpt-4o-mini\"\n",
+ "db_name = \"vector_db\""
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 5,
+ "id": "ee78efcb-60fe-449e-a944-40bab26261af",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# Load environment variables in a file called .env\n",
+ "\n",
+ "load_dotenv(override=True)\n",
+ "os.environ['OPENAI_API_KEY'] = os.getenv('OPENAI_API_KEY', 'your-key-if-not-using-env')"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 8,
+ "id": "730711a9-6ffe-4eee-8f48-d6cfb7314905",
+ "metadata": {},
+ "outputs": [
+ {
+ "ename": "NameError",
+ "evalue": "name 'DirectoryLoader' is not defined",
+ "output_type": "error",
+ "traceback": [
+ "\u001b[31m---------------------------------------------------------------------------\u001b[39m",
+ "\u001b[31mNameError\u001b[39m Traceback (most recent call last)",
+ "\u001b[36mCell\u001b[39m\u001b[36m \u001b[39m\u001b[32mIn[8]\u001b[39m\u001b[32m, line 14\u001b[39m\n\u001b[32m 12\u001b[39m \u001b[38;5;28;01mfor\u001b[39;00m folder \u001b[38;5;129;01min\u001b[39;00m folders:\n\u001b[32m 13\u001b[39m doc_type = os.path.basename(folder)\n\u001b[32m---> \u001b[39m\u001b[32m14\u001b[39m loader = \u001b[43mDirectoryLoader\u001b[49m(folder, glob=\u001b[33m\"\u001b[39m\u001b[33m**/*.md\u001b[39m\u001b[33m\"\u001b[39m, loader_cls=TextLoader, loader_kwargs=text_loader_kwargs)\n\u001b[32m 15\u001b[39m folder_docs = loader.load()\n\u001b[32m 16\u001b[39m \u001b[38;5;28;01mfor\u001b[39;00m doc \u001b[38;5;129;01min\u001b[39;00m folder_docs:\n",
+ "\u001b[31mNameError\u001b[39m: name 'DirectoryLoader' is not defined"
+ ]
+ }
+ ],
+ "source": [
+ "# Read in documents using LangChain's loaders\n",
+ "# Take everything in all the sub-folders of our knowledgebase\n",
+ "\n",
+ "folders = glob.glob(\"knowledge-base/*\")\n",
+ "\n",
+ "# With thanks to CG and Jon R, students on the course, for this fix needed for some users \n",
+ "text_loader_kwargs = {'encoding': 'utf-8'}\n",
+ "# If that doesn't work, some Windows users might need to uncomment the next line instead\n",
+ "# text_loader_kwargs={'autodetect_encoding': True}\n",
+ "\n",
+ "documents = []\n",
+ "for folder in folders:\n",
+ " doc_type = os.path.basename(folder)\n",
+ " loader = DirectoryLoader(folder, glob=\"**/*.md\", loader_cls=TextLoader, loader_kwargs=text_loader_kwargs)\n",
+ " folder_docs = loader.load()\n",
+ " for doc in folder_docs:\n",
+ " doc.metadata[\"doc_type\"] = doc_type\n",
+ " documents.append(doc)"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "7310c9c8-03c1-4efc-a104-5e89aec6db1a",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "text_splitter = CharacterTextSplitter(chunk_size=1000, chunk_overlap=200)\n",
+ "chunks = text_splitter.split_documents(documents)"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "cd06e02f-6d9b-44cc-a43d-e1faa8acc7bb",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "len(chunks)"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "2c54b4b6-06da-463d-bee7-4dd456c2b887",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "doc_types = set(chunk.metadata['doc_type'] for chunk in chunks)\n",
+ "print(f\"Document types found: {', '.join(doc_types)}\")"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "id": "77f7d2a6-ccfa-425b-a1c3-5e55b23bd013",
+ "metadata": {},
+ "source": [
+ "## A sidenote on Embeddings, and \"Auto-Encoding LLMs\"\n",
+ "\n",
+ "We will be mapping each chunk of text into a Vector that represents the meaning of the text, known as an embedding.\n",
+ "\n",
+ "OpenAI offers a model to do this, which we will use by calling their API with some LangChain code.\n",
+ "\n",
+ "This model is an example of an \"Auto-Encoding LLM\" which generates an output given a complete input.\n",
+ "It's different to all the other LLMs we've discussed today, which are known as \"Auto-Regressive LLMs\", and generate future tokens based only on past context.\n",
+ "\n",
+ "Another example of an Auto-Encoding LLMs is BERT from Google. In addition to embedding, Auto-encoding LLMs are often used for classification.\n",
+ "\n",
+ "### Sidenote\n",
+ "\n",
+ "In week 8 we will return to RAG and vector embeddings, and we will use an open-source vector encoder so that the data never leaves our computer - that's an important consideration when building enterprise systems and the data needs to remain internal."
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "78998399-ac17-4e28-b15f-0b5f51e6ee23",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# Put the chunks of data into a Vector Store that associates a Vector Embedding with each chunk\n",
+ "# Chroma is a popular open source Vector Database based on SQLLite\n",
+ "\n",
+ "# embeddings = OpenAIEmbeddings()\n",
+ "\n",
+ "# If you would rather use the free Vector Embeddings from HuggingFace sentence-transformers\n",
+ "# Then replace embeddings = OpenAIEmbeddings()\n",
+ "# with:\n",
+ "# from langchain.embeddings import HuggingFaceEmbeddings\n",
+ "# embeddings = HuggingFaceEmbeddings(model_name=\"sentence-transformers/all-MiniLM-L6-v2\",show_progress=False # you can set this False to hide the download bar)\n",
+ "\n",
+ "embeddings = HuggingFaceEmbeddings(model_name=\"sentence-transformers/all-MiniLM-L6-v2\")\n",
+ " \n",
+ "# Delete if already exists\n",
+ "\n",
+ "if os.path.exists(db_name):\n",
+ " Chroma(persist_directory=db_name, embedding_function=embeddings).delete_collection()\n",
+ "\n",
+ "# Create vectorstore\n",
+ "\n",
+ "vectorstore = Chroma.from_documents(documents=chunks, embedding=embeddings, persist_directory=db_name)\n",
+ "print(f\"Vectorstore created with {vectorstore._collection.count()} documents\")"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "057868f6-51a6-4087-94d1-380145821550",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# Get one vector and find how many dimensions it has\n",
+ "\n",
+ "collection = vectorstore._collection\n",
+ "sample_embedding = collection.get(limit=1, include=[\"embeddings\"])[\"embeddings\"][0]\n",
+ "dimensions = len(sample_embedding)\n",
+ "print(f\"The vectors have {dimensions:,} dimensions\")"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "id": "b0d45462-a818-441c-b010-b85b32bcf618",
+ "metadata": {},
+ "source": [
+ "## Visualizing the Vector Store\n",
+ "\n",
+ "Let's take a minute to look at the documents and their embedding vectors to see what's going on."
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "b98adf5e-d464-4bd2-9bdf-bc5b6770263b",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# Prework\n",
+ "\n",
+ "result = collection.get(include=['embeddings', 'documents', 'metadatas'])\n",
+ "vectors = np.array(result['embeddings'])\n",
+ "documents = result['documents']\n",
+ "doc_types = [metadata['doc_type'] for metadata in result['metadatas']]\n",
+ "colors = [['blue', 'green', 'red', 'orange'][['products', 'employees', 'contracts', 'company'].index(t)] for t in doc_types]"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "427149d5-e5d8-4abd-bb6f-7ef0333cca21",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# We humans find it easier to visalize things in 2D!\n",
+ "# Reduce the dimensionality of the vectors to 2D using t-SNE\n",
+ "# (t-distributed stochastic neighbor embedding)\n",
+ "\n",
+ "tsne = TSNE(n_components=2, random_state=42)\n",
+ "reduced_vectors = tsne.fit_transform(vectors)\n",
+ "\n",
+ "# Create the 2D scatter plot\n",
+ "fig = go.Figure(data=[go.Scatter(\n",
+ " x=reduced_vectors[:, 0],\n",
+ " y=reduced_vectors[:, 1],\n",
+ " mode='markers',\n",
+ " marker=dict(size=5, color=colors, opacity=0.8),\n",
+ " text=[f\"Type: {t}
Text: {d[:100]}...\" for t, d in zip(doc_types, documents)],\n",
+ " hoverinfo='text'\n",
+ ")])\n",
+ "\n",
+ "fig.update_layout(\n",
+ " title='2D Chroma Vector Store Visualization',\n",
+ " scene=dict(xaxis_title='x',yaxis_title='y'),\n",
+ " width=800,\n",
+ " height=600,\n",
+ " margin=dict(r=20, b=10, l=10, t=40)\n",
+ ")\n",
+ "\n",
+ "fig.show()"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "id": "e1418e88-acd5-460a-bf2b-4e6efc88e3dd",
+ "metadata": {},
+ "outputs": [],
+ "source": [
+ "# Let's try 3D!\n",
+ "\n",
+ "tsne = TSNE(n_components=3, random_state=42)\n",
+ "reduced_vectors = tsne.fit_transform(vectors)\n",
+ "\n",
+ "# Create the 3D scatter plot\n",
+ "fig = go.Figure(data=[go.Scatter3d(\n",
+ " x=reduced_vectors[:, 0],\n",
+ " y=reduced_vectors[:, 1],\n",
+ " z=reduced_vectors[:, 2],\n",
+ " mode='markers',\n",
+ " marker=dict(size=5, color=colors, opacity=0.8),\n",
+ " text=[f\"Type: {t}
Text: {d[:100]}...\" for t, d in zip(doc_types, documents)],\n",
+ " hoverinfo='text'\n",
+ ")])\n",
+ "\n",
+ "fig.update_layout(\n",
+ " title='3D Chroma Vector Store Visualization',\n",
+ " scene=dict(xaxis_title='x', yaxis_title='y', zaxis_title='z'),\n",
+ " width=900,\n",
+ " height=700,\n",
+ " margin=dict(r=20, b=10, l=10, t=40)\n",
+ ")\n",
+ "\n",
+ "fig.show()"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "id": "9468860b-86a2-41df-af01-b2400cc985be",
+ "metadata": {},
+ "source": [
+ "# Time to use LangChain to bring it all together"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "id": "8ba8a5e7-965d-4770-a12d-532aff50c4b5",
+ "metadata": {},
+ "source": [
+ "
\n",
+ " \n",
+ " | \n",
+ " \n",
+ " PLEASE READ ME! Ignoring the Deprecation Warning\n", + " When you run the next cell, you will get a LangChainDeprecationWarning \n", + " about the simple way we use LangChain memory. They ask us to migrate to their new approach for memory. \n", + " I feel quite conflicted about this. The new approach involves moving to LangGraph and getting deep into their ecosystem.\n", + " There's a fair amount of learning and coding in LangGraph, frankly without much benefit in our case.\n", + " I'm going to think about whether/how to incorporate it in the course, but for now please ignore the Depreciation Warning and\n", + " use the code as is; LangChain are not expected to remove ConversationBufferMemory any time soon.\n", + " \n", + " | \n",
+ "