Update app.py

app.py

@@ -30,6 +30,9 @@ model.load_state_dict(state_dict, strict=False)
 model.eval()
 
 def predict(im):
+    if im is None:
+        return None
+        
     x = torch.tensor(im, dtype=torch.float32).unsqueeze(0).unsqueeze(0) / 255.
 
     with torch.no_grad():