anchor.diff:  
         pcmsolver = callPackage ./pcmsolver {};
   
  -      psi4 = super.python3Packages.toPythonApplication self.python3Packages.psi4;
  -      psi4Unstable = super.python3Packages.toPythonApplication self.python3Packages.psi4Unstable;
  +      psi4 = super.python3.pkgs.toPythonApplication self.python3.pkgs.psi4;
  +      psi4Unstable = super.python3.pkgs.toPythonApplication self.python3.pkgs.psi4Unstable;
   
         qdng = callPackage ./qdng { protobuf=super.protobuf3_11; };
   
  
positive.code:       };
  
        # fix a bug in the header file, which causes bagel to fail
        libxc = self_.libxc.overrideDerivation (oa: {
          postFixup = ''
            sed -i '/#include "config.h"/d' $out/include/xc.h
          '';
  
negative.code:       libcint3 = callPackage ./libcint { };
  
        libefp = callPackage ./libefp {};
  
        libint1 = callPackage ./libint/1.nix { };
  
        libint2 = callPackage ./libint { inherit optAVX; };
  
  