diff --git a/litellm/tests/test_custom_callback_router.py b/litellm/tests/test_custom_callback_router.py
index 8a3ad1630..bd7b38bf7 100644
--- a/litellm/tests/test_custom_callback_router.py
+++ b/litellm/tests/test_custom_callback_router.py
@@ -51,17 +51,17 @@ class CompletionCustomHandler(CustomLogger): # https://docs.litellm.ai/docs/obse
             assert isinstance(kwargs['messages'], list) 
             assert isinstance(kwargs['optional_params'], dict)
             assert isinstance(kwargs['litellm_params'], dict) 
-            assert isinstance(kwargs['start_time'], Optional[datetime])
+            assert isinstance(kwargs['start_time'], (datetime, type(None)))
             assert isinstance(kwargs['stream'], bool)
-            assert isinstance(kwargs['user'], Optional[str])
+            assert isinstance(kwargs['user'], (str, type(None)))
             ### ROUTER-SPECIFIC KWARGS
             assert isinstance(kwargs["litellm_params"]["metadata"], dict)
             assert isinstance(kwargs["litellm_params"]["metadata"]["model_group"], str)
             assert isinstance(kwargs["litellm_params"]["metadata"]["deployment"], str)
             assert isinstance(kwargs["litellm_params"]["model_info"], dict)
             assert isinstance(kwargs["litellm_params"]["model_info"]["id"], str)
-            assert isinstance(kwargs["litellm_params"]["proxy_server_request"], Optional[str])
-            assert isinstance(kwargs["litellm_params"]["preset_cache_key"], Optional[str])
+            assert isinstance(kwargs["litellm_params"]["proxy_server_request"], (str, type(None)))
+            assert isinstance(kwargs["litellm_params"]["preset_cache_key"], (str, type(None)))
             assert isinstance(kwargs["litellm_params"]["stream_response"], dict)
         except Exception as e: 
             print(f"Assertion Error: {traceback.format_exc()}")