What standard libraries or modules are built into FastAPI for working with various functions?

FastAPI uses several built-in modules and libraries for various tasks:

• Pydantic — for data validation and serialization (request and response models).
• Starlette — an asynchronous web framework on which FastAPI is built, providing routing, middleware, WebSocket, etc.
• typing — Python's standard module for type annotations, actively used for describing parameter and return types.
• dataclasses — for convenient creation of data classes.
• uvicorn (often used together) — an ASGI server for running the application.

FastAPI also integrates with OAuth2, CORS, BackgroundTasks, and other features through built-in tools and dependencies.