anchor.diff:  }:
   
   buildPythonPackage rec {
  -  name = "${pname}-${version}";
     pname = "nimfa";
     version = "1.3.1";
   
  
positive.code: { stdenv
  , buildPythonPackage
  , fetchPypi
  , numpy
  , scipy
  , matplotlib
  
negative.code:   };
  
    propagatedBuildInputs = [ numpy scipy ];
    checkInputs = [ matplotlib pytest ];
    doCheck = !isPy3k;  # https://github.com/marinkaz/nimfa/issues/42
  
    meta = with stdenv.lib; {
      description = "Nonnegative matrix factorization library";
  