from fastapi import FastAPI from pydantic import BaseModel app = FastAPI() class Item(BaseModel): name: str description: str | None = None price: float tax: float | None = None tags: set[str] = set() @app.post("/items/", tags=["items"]) async def create_item(item: Item) -> Item: return item @app.get("/items/", tags=["items"]) async def read_items(): return [{"name": "Foo", "price": 42}] @app.get("/users/", tags=["users"]) async def read_users(): return [{"username": "johndoe"}]