use f string

app.py

@@ -46,7 +46,7 @@ def evaluation(predictions, metrics) -> str:
     combined.add_batch(predictions=predicted, references=references)
     outputs = combined.compute()
 
-    return "Your metrics are as follows: \n" + outputs
+    return f"Your metrics are as follows: \n {outputs}"
 
 
 # gr.Interface(