pythonPackages.pymatgen: add import check

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

@@ -52,6 +52,7 @@ buildPythonPackage rec {
 
   # No tests in pypi tarball.
   doCheck = false;
+  pythonImportsCheck = [ "pymatgen" ];
 
   meta = with lib; {
     description = "A robust materials analysis code that defines core object representations for structures and molecules";