add duplicate merge

user-friendly-metrics.py

@@ -288,6 +288,7 @@ def per_sequence_to_global(metrics_dict):
         for model in metrics_dict[sequence]:
             if model not in global_metrics:
                 global_metrics[model] = metrics_dict[sequence][model]
-            global_metrics[model] = sum_dicts(global_metrics[model], metrics_dict[sequence][model])
+            else:
+                global_metrics[model] = sum_dicts(global_metrics[model], metrics_dict[sequence][model])
 
     return global_metrics