python27Full = pkgs.python27Full.override {
  extraLibs = with pkgs.pythonPackages; [pkgs.pylint pkgs.scons];
  postBuild = ''
    cd ${pkgs.pylint}/bin
    for i in *; do
      rm $out/bin/$i
      sed -r -e "s|^exec |exec $out/bin/python -- |" <$i >$out/bin/$i
      chmod +x $out/bin/$i
    done;
  '';
};

$ nix-env -p /tmp/yo -iA python27Full
replacing old `python-2.7.6-wrapper'
installing `python-2.7.6-wrapper'
these derivations will be built:
  /nix/store/k6rd60c4xmjp9590blifa2603ygpqzc3-python-2.7.6-wrapper.drv
building path(s) `/nix/store/hk8nc4bzfcrcpxgdi237x9mnwbpvkn2p-python-2.7.6-wrapper'
building /nix/store/hk8nc4bzfcrcpxgdi237x9mnwbpvkn2p-python-2.7.6-wrapper
collision between `/nix/store/5p6p5p2rz0x04vhzpvj66zpd7kqx2cw6-python2.7-logilab-astng-0.24.1/bin/pytest' and `/nix/store/ib2jamy5n1i9wmb1pb9lbw3rwkc0pfbn-python2.7-logilab-common-0.58.2/bin/pytest' at /nix/store/9z6d76pz8rr7gci2n3igh5dqi7ac5xqj-builder.pl line 72.
builder for `/nix/store/k6rd60c4xmjp9590blifa2603ygpqzc3-python-2.7.6-wrapper.drv' failed with exit code 2
error: build of `/nix/store/k6rd60c4xmjp9590blifa2603ygpqzc3-python-2.7.6-wrapper.drv' failed