📝 Update source examples and docs from Python 3.9 to 3.10 (#14900)

docs_src/using_request_directly/tutorial001_py310.py

@@ -0,0 +1,9 @@
+from fastapi import FastAPI, Request
+
+app = FastAPI()
+
+
+@app.get("/items/{item_id}")
+def read_root(item_id: str, request: Request):
+    client_host = request.client.host
+    return {"client_host": client_host, "item_id": item_id}