diff --git a/tests/test_callbacks_on_proxy.py b/tests/test_callbacks_on_proxy.py
index 70cd3ca25d..7d48518b96 100644
--- a/tests/test_callbacks_on_proxy.py
+++ b/tests/test_callbacks_on_proxy.py
@@ -100,9 +100,9 @@ async def test_check_num_callbacks():
     """
     Test 1:  num callbacks should NOT increase over time
     -> check current callbacks
-    -> sleep for 30s
+    -> sleep for 30 seconds
     -> check current callbacks
-    -> sleep for 30s
+    -> sleep for 30 seconds
     -> check current callbacks
     """
     import uuid