diff --git a/tests_asyncio/test_subscribe.py b/tests_asyncio/test_subscribe.py
index ed3f83fd..bf985d58 100644
--- a/tests_asyncio/test_subscribe.py
+++ b/tests_asyncio/test_subscribe.py
@@ -1,13 +1,14 @@
 from pytest import mark
 
-from datetime import datetime
 from graphene import ObjectType, Int, String, Schema, Field
 
+
 class Query(ObjectType):
     hello = String()
 
     def resolve_hello(root, info):
-        return 'Hello, world!'
+        return "Hello, world!"
+
 
 class Subscription(ObjectType):
     count_to_ten = Field(Int)
@@ -16,15 +17,17 @@ class Subscription(ObjectType):
         count = 0
         while count < 10:
             count += 1
-            yield { 'count_to_ten': count }
+            yield {"count_to_ten": count}
+
 
 schema = Schema(query=Query, subscription=Subscription)
 
+
 @mark.asyncio
 async def test_subscription():
-    subscription = 'subscription { countToTen }'
+    subscription = "subscription { countToTen }"
     result = await schema.subscribe(subscription)
     count = 0
     async for item in result:
-        count = item.data['countToTen']
+        count = item.data["countToTen"]
     assert count == 10