diff --git a/aiohttp_session/redis_storage.py b/aiohttp_session/redis_storage.py
index 111f1a8f..5088c491 100644
--- a/aiohttp_session/redis_storage.py
+++ b/aiohttp_session/redis_storage.py
@@ -55,7 +55,7 @@ def __init__(
         if REDIS_VERSION < (4, 3):
             raise RuntimeError("redis<4.3 is not supported")
         self._key_factory = key_factory
-        if not isinstance(redis_pool, aioredis.Redis):
+        if not isinstance(redis_pool, aioredis.Redis):  # type: ignore[unreachable]
             raise TypeError(f"Expected redis.asyncio.Redis got {type(redis_pool)}")
         self._redis = redis_pool