diff --git a/check_params.py b/check_params.py
new file mode 100644
index 0000000000..df8719546d
--- /dev/null
+++ b/check_params.py
@@ -0,0 +1,7 @@
+from decimal import Decimal
+
+from fastapi import Query
+
+
+def create_item(price: Decimal = Query(..., max_digits=5, decimal_places=2)):
+    return {"price": price}
diff --git a/docs/en/docs/advanced/async-tests.md b/docs/en/docs/advanced/async-tests.md
index c7ec5e9e29..06d474afc9 100644
--- a/docs/en/docs/advanced/async-tests.md
+++ b/docs/en/docs/advanced/async-tests.md
@@ -94,6 +94,7 @@ As the testing function is now asynchronous, you can now also call (and `await`)
 
 /// tip
 
+If you encounter a `RuntimeError: Task attached to a different loop` when integrating asynchronous function calls in your tests (e.g. when using <a href="https://stackoverflow.com/questions/41584243/runtimeerror-task-attached-to-a-different-loop" class="external-link" target="_blank">MongoDB's MotorClient</a>), remember to instantiate objects that need an event loop only within async functions, for example, using a lifespan async context manager.
 If you encounter a `RuntimeError: Task attached to a different loop` when integrating asynchronous function calls in your tests (e.g. when using [MongoDB's MotorClient](https://stackoverflow.com/questions/41584243/runtimeerror-task-attached-to-a-different-loop)), remember to instantiate objects that need an event loop only within async functions, e.g. an `@app.on_event("startup")` callback.
 
 ///
diff --git a/docs_src/app_testing/tutorial003.py b/docs_src/app_testing/tutorial003.py
new file mode 100644
index 0000000000..3ff87cb2a7
--- /dev/null
+++ b/docs_src/app_testing/tutorial003.py
@@ -0,0 +1,30 @@
+from contextlib import asynccontextmanager
+from typing import Any
+
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+# Use typing.Dict for compatibility with older Python versions
+items: dict[str, Any] = {}
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    items["foo"] = {"name": "Fighters"}
+    items["bar"] = {"name": "Tenders"}
+    yield
+
+
+app = FastAPI(lifespan=lifespan)
+
+
+@app.get("/items/{item_id}")
+async def read_items(item_id: str):
+    return items[item_id]
+
+
+def test_read_items():
+    with TestClient(app) as client:
+        response = client.get("/items/foo")
+        assert response.status_code == 200
+        assert response.json() == {"name": "Fighters"}
diff --git a/docs_src/app_testing/tutorial003_py310.py b/docs_src/app_testing/tutorial003_py310.py
index ca6b45ce03..07bf7f2367 100644
--- a/docs_src/app_testing/tutorial003_py310.py
+++ b/docs_src/app_testing/tutorial003_py310.py
@@ -1,15 +1,19 @@
+from contextlib import asynccontextmanager
+
 from fastapi import FastAPI
 from fastapi.testclient import TestClient
 
-app = FastAPI()
-
 items = {}
 
 
-@app.on_event("startup")
-async def startup_event():
+@asynccontextmanager
+async def lifespan(app: FastAPI):
     items["foo"] = {"name": "Fighters"}
     items["bar"] = {"name": "Tenders"}
+    yield
+
+
+app = FastAPI(lifespan=lifespan)
 
 
 @app.get("/items/{item_id}")
diff --git a/tests/test_tutorial/test_testing/test_tutorial003.py b/tests/test_tutorial/test_testing/test_tutorial003.py
index 196fc45559..b455bc949f 100644
--- a/tests/test_tutorial/test_testing/test_tutorial003.py
+++ b/tests/test_tutorial/test_testing/test_tutorial003.py
@@ -1,7 +1,11 @@
-import pytest
+from docs_src.app_testing import tutorial003, tutorial003_py310
 
 
-def test_main():
-    with pytest.warns(DeprecationWarning):
-        from docs_src.app_testing.tutorial003_py310 import test_read_items
-    test_read_items()
+def test_tutorial003():
+    # This covers the base version (tutorial003.py)
+    tutorial003.test_read_items()
+
+
+def test_tutorial003_py310():
+    # This covers the modern version (tutorial003_py310.py)
+    tutorial003_py310.test_read_items()