* buildPythonPackage: added an argument `pythonPath' to specify Python

dependencies that are *not* propagated to the user environment
  (as opposed to `propagatedBuildInputs').  For instance, if you
  install `iotop', you typically don't want its Python dependencies
  polluting the user environment.
  
* buildPythonPackage: some cleanup (e.g. use function argument
  defaults instead of `if attrs ? foo then attrs.foo else []').

svn path=/nixpkgs/branches/modular-python/; revision=26571

pkgs/os-specific/linux/iotop/default.nix

@@ -9,7 +9,7 @@ buildPythonPackage rec {
     sha256 = "1dfvw3khr2rvqllvs9wad9ca3ld4i7szqf0ibq87rn36ickrf3ll";
   };
 
-  propagatedBuildInputs = [ pythonPackages.curses ];
+  pythonPath = [ pythonPackages.curses ];
 
   doCheck = false;