Development of Telegram Bots in Python from Scratch

Practical approaches to creating Telegram bots in Python using the aiogram framework are considered. The development stages are detailed—from installing the framework and launching the bot to complex interaction scenarios with the user. Recommendations for securely storing tokens and other data are provided. Message, command, and argument handling, output formatting, working with media files, buttons, and callbacks, project structure using routers, filters, and middleware are discussed. The use of finite state machines (FSM) and scenes for step-by-step dialogues, working in inline mode, displaying results, collecting statistics, and loading large volumes of data are demonstrated. Examples of payment integration with Telegram Stars, purchase verification and refund, error handling, and testing using pytest are provided.