Find python packages that are likely to fail when used through "nix-shell -p"

propagatedPython.nix

with builtins;
let 
  # evaluate expr, returning default on error
  tryDefault = expr: default:
     let res = (tryEval expr);
     in if res.success then res.value else default;

  
  isPython = pkg: pkg?name && (parseDrvName pkg.name).name == "python";
  hasPropagatedPython = pkg:
    (pkg?propagatedNativeBuildInputs &&
                (length (filter isPython pkg.propagatedNativeBuildInputs)) > 0)
  ;
  # Skip broken packages and packages that doesn't support the given python version
  validPythonPackage = pkg: tryDefault (pkg?disabled -> !pkg.disabled)
                                       false
  ;

in
rec {
   inherit tryDefault validPythonPackage hasPropagatedPython isPython;
   validPythonPackages = pkgs: (filter validPythonPackage
                                    (attrValues pkgs));
   withoutPropagatedPython = pkgs:
     filter
        (pkg: tryDefault (pkg?name && !(hasPropagatedPython pkg)) false)
        (validPythonPackages pkgs);
}

# run `nix-repl THISFILE.nix`
# :l <nixpkgs>
# builtins.map (pkg: pkg.name) (withoutPropagatedPython python2Packages)