diff --git a/tests/test_coder.py b/tests/test_coder.py
index b3fcdeaa4..0995b0fda 100644
--- a/tests/test_coder.py
+++ b/tests/test_coder.py
@@ -1,7 +1,9 @@
+import os
 import unittest
 from unittest.mock import MagicMock
 from aider.coder import Coder
 
+
 class TestCoder(unittest.TestCase):
     def test_check_for_file_mentions(self):
         # Mock the IO object
@@ -18,11 +20,12 @@ class TestCoder(unittest.TestCase):
         coder.repo = mock_repo
 
         # Call the check_for_file_mentions method
-        result = coder.check_for_file_mentions("Please check file1.txt and file2.py")
+        coder.check_for_file_mentions("Please check file1.txt and file2.py")
 
         # Check if coder.abs_fnames contains both files
         expected_files = {os.path.abspath("file1.txt"), os.path.abspath("file2.py")}
         self.assertEqual(coder.abs_fnames, expected_files)
 
+
 if __name__ == "__main__":
     unittest.main()