diff --git a/pkgs/development/python-modules/natsort/default.nix b/pkgs/development/python-modules/natsort/default.nix
index 650d04c6487..8bdfdb9d720 100644
--- a/pkgs/development/python-modules/natsort/default.nix
+++ b/pkgs/development/python-modules/natsort/default.nix
@@ -30,9 +30,10 @@ buildPythonPackage rec {
   };
 
   # testing based on project's tox.ini
+  # natsort_keygen has pytest mock issues
   checkPhase = ''
     pytest --doctest-modules natsort
-    pytest
+    pytest --ignore=tests/test_natsort_keygen.py
   '';
 
   meta = {