remove allow-untyped-defs for torch/_inductor/test_operators.py (pytorch#143436)

Pull Request resolved: pytorch#143436
Approved by: https://github.com/aorenste

Author: bobrenjc93

torch/_inductor/test_operators.py

@@ -1,4 +1,5 @@
-# mypy: allow-untyped-defs
+from typing import Any
+
 import torch.library
 from torch import Tensor
 from torch.autograd import Function
@@ -16,12 +17,13 @@
 
     class Realize(Function):
         @staticmethod
-        def forward(ctx, x):
+        def forward(ctx: object, x: Tensor) -> Tensor:
             return torch.ops._inductor_test.realize(x)
 
         @staticmethod
-        def backward(ctx, grad_output):
-            return grad_output
+        # types need to stay consistent with _SingleLevelFunction
+        def backward(ctx: Any, *grad_output: Any) -> Any:
+            return grad_output[0]
 
     def realize(x: Tensor) -> Tensor:
         return Realize.apply(x)