Update app.py

app.py

@@ -13,6 +13,8 @@ from keras.saving import register_keras_serializable
 from keras import layers
 from huggingface_hub import hf_hub_download
 from keras.applications.densenet import DenseNet121
+from concurrent.futures import ThreadPoolExecutor
+
 #from tensorflow_docs.vis import embed
 
 app = FastAPI()