diff --git a/userbenchmark/dynamo/dynamobench/_dynamo/utils.py b/userbenchmark/dynamo/dynamobench/_dynamo/utils.py
index d7a40fa2b..2fec4c5cf 100644
--- a/userbenchmark/dynamo/dynamobench/_dynamo/utils.py
+++ b/userbenchmark/dynamo/dynamobench/_dynamo/utils.py
@@ -37,19 +37,25 @@
     DefaultDict,
     Deque,
     Dict,
+    Iterable,
     Iterator,
     KeysView,
     List,
     Optional,
+    overload,
     Set,
     Tuple,
     Type,
+    TypeVar,
     Union,
     ValuesView,
 )
+from typing_extensions import TypeGuard
 
 from ..utils.hooks import RemovableHandle
 
+T = TypeVar("T")
+
 try:
     import numpy as np
 except ModuleNotFoundError:
@@ -498,6 +504,23 @@ def clear(self):
         self.values.clear()
 
 
+@overload
+def istype(obj: object, allowed_types: Type[T]) -> TypeGuard[T]:
+    ...
+
+
+@overload
+def istype(
+    obj: object, allowed_types: Tuple[Type[List[T]], Type[Tuple[T, ...]]]
+) -> TypeGuard[T]:
+    ...
+
+
+@overload
+def istype(obj: object, allowed_types: Iterable[type]) -> bool:
+    ...
+
+
 def istype(obj, allowed_types):
     """isinstance() without subclasses"""
     if isinstance(allowed_types, (tuple, list, set)):
@@ -631,7 +654,7 @@ def is_numpy_ndarray(value):
 
 def istensor(obj):
     """Check of obj is a tensor"""
-    tensor_list = (
+    tensor_list: Tuple[type, ...] = (
         torch.Tensor,
         torch.nn.Parameter,
         *config.traceable_tensor_subclasses,
@@ -1061,7 +1084,7 @@ def rot_n_helper(n):
     return fn
 
 
-common_constant_types = {
+common_constant_types: Set[type] = {
     int,
     float,
     complex,