Update app.py

app.py

@@ -162,7 +162,7 @@ def get_data():
     output.append({"gpus":get_gpus(), "total":{"total" : blockchain.get_total_gpu_mem(), "used":get_used_gpus(model_name)}, "chain":json_data+blockchain.chain})
 
     with open('./Chain_data.json', 'w') as outfile:
-        json.dump(output['chain'], outfile)
+        json.dump([output['chain']], outfile)
     return output