diff --git a/benchmark/problem_stats.py b/benchmark/problem_stats.py
index c231c2153..992b4cc28 100755
--- a/benchmark/problem_stats.py
+++ b/benchmark/problem_stats.py
@@ -160,13 +160,17 @@ def analyze_exercise_solutions(dirs=None, topn=None):
     print("\nSummary:")
     solved_at_least_once = len([ex for ex, models in exercise_solutions.items() if models])
     solved_by_none = never_solved
-    solved_by_all = len([ex for ex, models in exercise_solutions.items() if len(models) == total_models])
-    
+    solved_by_all = len(
+        [ex for ex, models in exercise_solutions.items() if len(models) == total_models]
+    )
+
     print(f"Total exercises solved at least once: {solved_at_least_once}")
     print(f"Never solved by any model: {solved_by_none}")
     print(f"Solved by all models: {solved_by_all}")
-    print(f"Total exercises: {len(all_exercises)} = {solved_by_none} (none) + {solved_by_all} (all) + "
-          f"{len(all_exercises) - solved_by_none - solved_by_all} (some)")
+    print(
+        f"Total exercises: {len(all_exercises)} = {solved_by_none} (none) + {solved_by_all} (all) +"
+        f" {len(all_exercises) - solved_by_none - solved_by_all} (some)"
+    )
 
 
 if __name__ == "__main__":