import wan only if gpu avalaible

gradio/vace.py

@@ -21,10 +21,10 @@ if not is_shared_ui and is_gpu_associated:
         local_dir = "./models/Wan2.1-VACE-1.3B"
     )
 
-sys.path.insert(0, os.path.sep.join(os.path.realpath(__file__).split(os.path.sep)[:-2]))
-import wan
-from wan import WanVace, WanVaceMP
-from wan.configs import WAN_CONFIGS, SIZE_CONFIGS
+    sys.path.insert(0, os.path.sep.join(os.path.realpath(__file__).split(os.path.sep)[:-2]))
+    import wan
+    from wan import WanVace, WanVaceMP
+    from wan.configs import WAN_CONFIGS, SIZE_CONFIGS
 
 css = """
 div#warning-duplicate {