How to get started with langchain

Python based dev container with using vs code remote explorer
Poetry install https://python-poetry.org/docs/#installing-with-the-official-installer

curl -sSL https://install.python-poetry.org | python3 -

  poetry add langchain-core
  poetry add langchain-community
  poetry add langchain-openai

Core Langchain Concepts:

from langchain_core.messages import AIMessage,HumanMessage, ToolMessage,BaseMessage
from langchain_core.tools import tool
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.runnables import Runnable, RunnableConfig
from langchain_core.utils.function_calling import convert_to_openai_function
from langgraph.prebuilt import ToolNode
from langgraph.graph import END, StateGraph, START
from langgraph.prebuilt import tools_condition
from langgraph.graph.message import AnyMessage, add_messages
from langgraph.graph import MessagesState, StateGraph, START
from langchain.agents import Tool
from langchain.utilities import GoogleSerperAPIWrapper
from langchain.chains import APIChain
from langchain.vectorstores import FAISS
from langchain.embeddings import OpenAIEmbeddings
from langchain.callbacks.base import AsyncCallbackHandler
from langchain.callbacks.manager import AsyncCallbackManager
from langchain.chains.conversation.memory import ConversationBufferMemory
from langchain.memory import ConversationBufferWindowMemory
from langchain.text_splitter import CharacterTextSplitter
from langchain.docstore.document import Document
from langchain.vectorstores import FAISS
from langchain.memory import ConversationBufferMemory

Name		Name	Last commit message	Last commit date
Latest commit History 4 Commits
.devcontainer		.devcontainer
.github		.github
__pycache__		__pycache__
.env		.env
.gitignore		.gitignore
Hotel_Alexandra.txt		Hotel_Alexandra.txt
data.txt		data.txt
gemeni_rag.py		gemeni_rag.py
langchain_agents.py		langchain_agents.py
langchain_chains.py		langchain_chains.py
langchain_memory.py		langchain_memory.py
langchain_messages.py		langchain_messages.py
langchain_prompts.py		langchain_prompts.py
langchain_rag_agent.py		langchain_rag_agent.py
langchain_tools.py		langchain_tools.py
langgraph_agent.py		langgraph_agent.py
langgraph_basic.py		langgraph_basic.py
langgraph_gemeni_agenticai_solar_rag.py		langgraph_gemeni_agenticai_solar_rag.py
llm_gemeni.py		llm_gemeni.py
main.py		main.py
openai_rag.py		openai_rag.py
openai_rag_faiss.py		openai_rag_faiss.py
poetry.lock		poetry.lock
pyproject.toml		pyproject.toml
readme.md		readme.md