fix

vllm/_custom_ops.py

@@ -1,6 +1,6 @@
 import contextlib
 import functools
-from typing import List, Optional, Tuple, Union
+from typing import TYPE_CHECKING, List, Optional, Tuple, Union
 
 import torch
 import torch.library
@@ -26,10 +26,15 @@
     import vllm._moe_C  # noqa: F401
     supports_moe_ops = True
 
-try:
-    import torch.library.register_fake
-except ImportError:
-    from torch.library import impl_abstract as register_fake
+if TYPE_CHECKING:
+
+    def register_fake(fn):
+        return lambda name: fn
+else:
+    try:
+        from torch.library import register_fake
+    except ImportError:
+        from torch.library import impl_abstract as register_fake
 
 
 def hint_on_error(fn):