Sync fastapi docs from 50fa3f7c on 2026-01-11

docs_src/dataclasses_/tutorial001_py39.py

@@ -0,0 +1,20 @@
+from dataclasses import dataclass
+from typing import Union
+
+from fastapi import FastAPI
+
+
+@dataclass
+class Item:
+    name: str
+    price: float
+    description: Union[str, None] = None
+    tax: Union[float, None] = None
+
+
+app = FastAPI()
+
+
+@app.post("/items/")
+async def create_item(item: Item):
+    return item