pytags -- a ctags script that seems to generate a goodly amount of information about python

default.nix

{ pkgs ? import <nixpkgs> {}
, ctags ? pkgs.ctags
, makeWrapper ? pkgs.makeWrapper
, makeBinPath ? pkgs.lib.makeBinPath
}:
pkgs.stdenv.mkDerivation {
    name = "pytags";

    buildInputs = [ ctags
                    makeWrapper
                  ];

    phases = [ "installPhase" ];

    src = ./.;

    installPhase = ''
        mkdir -p $out/bin
        cp $src/pytags.sh $out/bin/pytags.sh
        makeWrapper $out/bin/pytags.sh $out/bin/pytags --prefix PATH : ${makeBinPath [ctags]}
        '';
} 

pytags.sh

ctags -R --fields=+l --languages=python --python-kinds=-iv -f ./tags