This book describes how to create various NLP applications based on transformers using the Python Transformers library. You will get acquainted with the architecture of transformers and write your first program for working with models based on this advanced technology. Effective open source models for solving complex problems and test datasets will be presented to your attention; you will learn multilingual and cross-language word processing techniques, learn to optimize models, and learn how to achieve interpretability and explainability for these models.