Update app.py

app.py

@@ -83,7 +83,7 @@ def get_difficulty_parameters(difficulty_level):
                 "Test deep theoretical understanding"
             ],
             "example_style": "Similar to graduate qualifying exams or advanced competition problems",
-            "model": "claude-3-sonnet-20241022"
+            "model": "claude-3-5-sonnet-20241022"
         }
     }