LangChain Nebius Integration

This package provides LangChain integration for Nebius AI Studio, enabling seamless use of Nebius AI Studio's chat and embedding models within LangChain. It offers classes for chat models (ChatNebius), embedding models (NebiusEmbeddings), and a retriever (NebiusRetriever), facilitating common LLM application patterns like RAG. The current version is 0.1.3.