nThis book provides an ideal guide for Python developers who want to learn how to build applications with large language models. Authors Olivier Caelen and Marie-Alice Blete cover the main features and benefits of GPT-4 and GPT-3.5 models and explain how they work. Youll also get a step-by-step guide for developing applications using the OpenAI Python library, including text generation, Q&A, and smart assistants. n n Written in clear and concise language, Developing Apps with GPT-4 and ChatGPT includes easy-to-follow examples to help you understand and apply the concepts to your projects. Python code examples are available in a GitHub repository, and the book includes a glossary of key terms. Ready to harness the power of large language models in your applications? This book is a must. n n Youll learn: n n- Fundamentals and benefits of GPT-4 and GPT-3.5 models, including the main features and how they work n- How to integrate these models into Python-based applications, leveraging natural language processing capabilities and overcoming specific LLM-related challenges n- Examples of applications demonstrating the OpenAI API in Python for tasks including text generation, question answering, content summarization, classification, and more n- Advanced LLM topics such as prompt engineering, fine-tuning models for specific tasks, RAG, plug-ins, LangChain, LlamaIndex, GPTs, and assistants nOlivier Caelen is a machine learning researcher at Worldline and teaches machine learning courses at the University of Brussels. n n Marie-Alice Blete, a software architect and data engineer in Worldlines R&D department, is interested in performance and latency issues associated with AI solutions.n