anchor.diff:    propagatedBuildInputs = [
       numpy decorator imageio imageio-ffmpeg tqdm requests proglog
     ] ++ (stdenv.lib.optionals advancedProcessing [
  -    opencv scikitimage scikitlearn scipy matplotlib youtube-dl
  +    opencv3 scikitimage scikitlearn scipy matplotlib youtube-dl
     ]);
   
     meta = with stdenv.lib; {
  
positive.code: }:
  
  assert advancedProcessing -> (
    opencv != null && scikitimage != null && scikitlearn != null
    && scipy != null && matplotlib != null && youtube-dl != null);
  
  buildPythonPackage rec {
  
negative.code: , tqdm
  # Advanced image processing (triples size of output)
  , advancedProcessing ? false
  , opencv3 ? null
  , scikitimage ? null
  , scikitlearn ? null
  , scipy ? null
  