anchor.diff:  in buildPythonPackage rec {
     pname = "numpy";
     version = "1.18.0";
  +  format = "pyproject.toml";
   
     src = fetchPypi {
       inherit pname version;
  
positive.code:     sha256 = "a9d72d9abaf65628f0f31bbb573b7d9304e43b1e6bbae43149c17737a42764c4";
    };
  
    nativeBuildInputs = [ gfortran pytest ];
    buildInputs = [ blas ];
  
    patches = lib.optionals python.hasDistutilsCxxPatch [
  
negative.code: { lib
  , fetchPypi
  , python
  , buildPythonPackage
  , gfortran
  , pytest
  , blas
  , writeTextFile
  , isPyPy
  , cython
  , setuptoolsBuildHook
   }:
  
  let
    blasImplementation = lib.nameFromURL blas.name "-";
  