diff --git a/tests/conftest.py b/tests/conftest.py
index 0d82c97..e8180f6 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -20,7 +20,6 @@
 import json
 import logging
 import os
-import sys
 
 import elasticapm
 import pytest
@@ -75,7 +74,7 @@ def validator(data_json):
                             )
                         )
             if v.get("index") and list(data.keys())[v.get("index")] != k:
-                raise ValidationError(f"Key {k} is not at index {index}")
+                raise ValidationError(f"Key {k} is not at index {v.get('index')}")
 
         return data_json
 
diff --git a/tests/test_stdlib_formatter.py b/tests/test_stdlib_formatter.py
index 18cf555..62bc41b 100644
--- a/tests/test_stdlib_formatter.py
+++ b/tests/test_stdlib_formatter.py
@@ -22,7 +22,6 @@
 import json
 import time
 import random
-import sys
 import ecs_logging
 from io import StringIO