Update prims.py

Author: justinchuby

onnxscript/function_libs/torch_lib/ops/prims.py

@@ -14,7 +14,7 @@
 
 from typing import Optional, Sequence
 
-from onnxscript import INT64, ir
+from onnxscript import INT64
 from onnxscript.function_libs.torch_lib.ops import common as common_ops
 from onnxscript.function_libs.torch_lib.registration import torch_op
 from onnxscript.function_libs.torch_lib.tensor_typing import RealType, TTensor