diff --git a/Web/Python/vtkmodules/web/utils.py b/Web/Python/vtkmodules/web/utils.py
index 19925ef6ced3e93606e793343e7f79b9a027b3fa..1a49112a6adb90e249425d3b15f6e620cb032b46 100644
--- a/Web/Python/vtkmodules/web/utils.py
+++ b/Web/Python/vtkmodules/web/utils.py
@@ -1,8 +1,10 @@
 try:
     import numpy as np
 except ImportError:
-    raise RuntimeError("This module depends on the numpy module. Please make\
-sure that it is installed properly.")
+    raise ImportError(
+        "This module depends on the numpy module. Please make\
+sure that it is installed properly."
+    )
 
 import base64