diff --git a/pylops/utils/backend.py b/pylops/utils/backend.py
index d88ec830..4b6b506f 100644
--- a/pylops/utils/backend.py
+++ b/pylops/utils/backend.py
@@ -26,7 +26,7 @@
 ]
 
 from types import ModuleType
-from typing import Callable, Union
+from typing import Callable
 
 import numpy as np
 import numpy.typing as npt