diff --git a/pkgs/development/python-modules/robotframework-tools/default.nix b/pkgs/development/python-modules/robotframework-tools/default.nix
index 5e8ca33fffb..77a7fe13df9 100644
--- a/pkgs/development/python-modules/robotframework-tools/default.nix
+++ b/pkgs/development/python-modules/robotframework-tools/default.nix
@@ -1,7 +1,6 @@
 { lib
 , buildPythonPackage
 , fetchPypi
-, isPy3k
 , robotframework
 , moretools
 , pathpy