pythonPackages.clize: fix build

pkgs/development/python-modules/clize/default.nix

@@ -10,7 +10,7 @@
 , repeated_test
 , pygments
 , unittest2
-, pytest
+, pytestCheckHook
 }:
 
 buildPythonPackage rec {
@@ -22,12 +22,17 @@ buildPythonPackage rec {
     sha256 = "f54dedcf6fea90a3e75c30cb65e0ab1e832760121f393b8d68edd711dbaf7187";
   };
 
+  # Remove overly restrictive version constraints
+  postPatch = ''
+    substituteInPlace setup.py --replace "attrs>=19.1.0,<20" "attrs"
+  '';
+
   checkInputs = [
+    pytestCheckHook
     dateutil
     pygments
     repeated_test
     unittest2
-    pytest
   ];
 
   propagatedBuildInputs = [
@@ -38,14 +43,11 @@ buildPythonPackage rec {
     six
   ];
 
-  checkPhase = ''
-    pytest
-  '';
+  pythonImportsCheck = [ "clize" ];
 
   meta = with stdenv.lib; {
     description = "Command-line argument parsing for Python";
     homepage = "https://github.com/epsy/clize";
     license = licenses.mit;
   };
-
 }