anchor.diff:  , buildPythonPackage
   , fetchFromGitHub
   # , cplex
  -, cvxopt
  +, cvxpy
   , dlx
   , docplex
   , fastdtw
  
positive.code:         "You must install it yourself via pip or add it to your environment from the Nix User Repository." \
          "', ImportWarning)\n" \
        >> qiskit/optimization/__init__.py
  
    '';
  
    postInstall = "rm -rf $out/${python.sitePackages}/docs";  # Remove docs dir b/c it can cause conflicts.
  
negative.code: 
  buildPythonPackage rec {
    pname = "qiskit-aqua";
    version = "0.7.3";
  
    disabled = pythonOlder "3.5";
  
  