Make the runtime counter var global.

app.py

@@ -68,7 +68,7 @@ def predict(image, resolution, weights_file):
     global birefnet
     # Load BiRefNet with chosen weights
     _weights_file = '/'.join(('zhengpeng7', usage_to_weights_file[weights_file] if weights_file is not None else usage_to_weights_file['General']))
-    counter_runtime += 1
+    global counter_runtime; counter_runtime += 1
     print('Using weights: {} in runtime {}'.format(_weights_file, counter_runtime))
     birefnet = AutoModelForImageSegmentation.from_pretrained(_weights_file, trust_remote_code=True)
     birefnet.to(device)