anchor.diff:  , sympy
   , matplotlib
   , reportlab
  +, sphinx
   , pytest
   , pytest-randomly
   , glibcLocales
  
positive.code:     matplotlib
      # pens
      reportlab
    ];
  
    preCheck = ''
  
negative.code: 
  buildPythonPackage rec {
    pname = "fonttools";
    version = "4.18.2";
    disabled = pythonOlder "3.6";
  
    src = fetchFromGitHub {
      owner  = pname;
      repo   = pname;
      rev    = version;
      sha256 = "0h750gvwpsp7fpmgfwkx93gkaf0m1s698g6r7n4xlaji563nlkiv";
    };
  
    # all dependencies are optional, but
  