Nix, with python, bad expression

pythonMessedUp.nix

#this is a bad version of a python NIX expression, with pythonIRClib dependency. 

#arguments for the nix expression, syntax is { argname ? defaultvalue, argname ? defaultvalue }
{ stdenv ? (import <nixpkgs> {}).stdenv ,python ? (import <nixpkgs> {}).python, pythonPackages ? (import <nixpkgs> {}).pythonPackages, pythonIRClib ? (import <nixpkgs> {}).pythonIRClib }:
 
 
stdenv.mkDerivation {
  name = "python-nix";
  version = "0.1.0.0";
  src = ./.;
  buildDepends = [ pythonIRClib ]; #buildDepends is wrong unless working with Haskell.
  buildTools = [ python ];
  PYTHONPATH="${pythonIRClib}/lib/python2.7/site-packages";
}