Update app.py

app.py

@@ -17,6 +17,8 @@ import os
 
 # }
 def array_to_image_path(image_array):
+    if image_array is None:
+        raise ValueError("No image provided. Please upload an image before submitting.")
     # Convert numpy array to PIL Image
     img = Image.fromarray(np.uint8(image_array))