diff --git a/pytest_asyncio/plugin.py b/pytest_asyncio/plugin.py
index dfcf471c..7a7c8dd5 100644
--- a/pytest_asyncio/plugin.py
+++ b/pytest_asyncio/plugin.py
@@ -460,7 +460,7 @@ def pytest_runtest_setup(item: pytest.Item) -> None:
 
 
 @pytest.fixture
-def event_loop(request: pytest.FixtureRequest) -> Iterator[asyncio.AbstractEventLoop]:
+def event_loop(request: "pytest.FixtureRequest") -> Iterator[asyncio.AbstractEventLoop]:
     """Create an instance of the default event loop for each test case."""
     loop = asyncio.get_event_loop_policy().new_event_loop()
     yield loop