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

docs_src/encoder/tutorial001_py39.py

@@ -0,0 +1,23 @@
+from datetime import datetime
+from typing import Union
+
+from fastapi import FastAPI
+from fastapi.encoders import jsonable_encoder
+from pydantic import BaseModel
+
+fake_db = {}
+
+
+class Item(BaseModel):
+    title: str
+    timestamp: datetime
+    description: Union[str, None] = None
+
+
+app = FastAPI()
+
+
+@app.put("/items/{id}")
+def update_item(id: str, item: Item):
+    json_compatible_item_data = jsonable_encoder(item)
+    fake_db[id] = json_compatible_item_data