fix AtomArray display

app.py

@@ -93,7 +93,7 @@ def test_rfd3_from_notebook():
         for idx, data in outputs.items():
             return_str += f"Batch {idx}: {len(data)} structure(s)\n"
             for i, struct in enumerate(data):
-                return_str += f"Structure {i+1}:\n"
+                return_str += f"Structure {i+1}: {struct.atom_array.array_length()} Atoms\n"
                 return_str += struct.atom_array
         return return_str
     except Exception as e: