anchor.diff:  { lib
  +, stdenv
   , pythonOlder
   , buildPythonPackage
   , fetchFromGitHub
  
positive.code:     pushd $PACKAGEDIR
    '';
    postCheck = ''
      rm -rf test
      rm -rf examples
      popd
    '';
  
  
negative.code:     "test/python/classical_function_compiler/"
    ];
    disabledTests = [
      # Not working on matplotlib >= 3.4.0, checks images match.
      "test_plot_circuit_layout"
  
      # Flaky tests
      "test_cx_equivalence"
      "test_pulse_limits"
      "test_1q_random"
    ] ++ lib.optionals (!withClassicalFunctionCompiler) [
      "TestPhaseOracle"
    ] ++ lib.optionals stdenv.isAarch64 [
      "test_circuit_init" # failed on aarch64, https://gist.github.com/r-rmcgibbo/c2e173d43ced4f6954811004f6b5b842
    ]
    # Disabling slow tests for build constraints
    ++ [
  