Update app.py

app.py

@@ -241,8 +241,8 @@ def phylogenetic_placement(sequence: str, mafft_cmd: str, iqtree_cmd: str):
         if 'query_fasta' in locals() and os.path.exists(query_fasta):
             try:
                 os.unlink(query_fasta)
-            except Exception as e:  # Fixed bare 'except'
-                logger.warning(f"Failed to clean up {query_fasta}: {e}")
+            except Exception as cleanup_error:
+                logger.warning(f"Failed to clean up {query_fasta}: {cleanup_error}")
 
 def analyze_sequence_for_tree(sequence: str, matching_percentage: float):
     try: