diff --git a/pkgs/development/python-modules/pyls-mypy/default.nix b/pkgs/development/python-modules/pyls-mypy/default.nix
index b9cf9738ed4..eaf069c8ccb 100644
--- a/pkgs/development/python-modules/pyls-mypy/default.nix
+++ b/pkgs/development/python-modules/pyls-mypy/default.nix
@@ -1,6 +1,6 @@
 { lib, buildPythonPackage, fetchFromGitHub, isPy27
 , future, python-language-server, mypy, configparser
-, pytestCheckHook, mock, isPy3k, pytestcov, coverage
+, pytestCheckHook, mock, pytestcov, coverage
 , fetchpatch
 }: