anchor.diff:  { lib
   , buildPythonPackage
  -, fetchPypi
  +, fetchFromGitHub
   , nose
   }:
   
  
positive.code: 
    meta = with lib; {
      description = "Patch python built-in objects";
      homepage = "https://pypi.python.org/pypi/forbiddenfruit";
      license = licenses.mit;
    };
  
  
negative.code:   version = "0.1.4";
    pname = "forbiddenfruit";
  
    src = fetchFromGitHub {
      owner = "clarete";
      repo = "forbiddenfruit";
      rev = version;
      sha256 = "16chhrxbbmg6lfbzm532fq0v00z8qihcsj0kg2b5jlgnb6qijwn8";
    };
  
    checkInputs = [ nose ];
  
    preBuild = ''
      export FFRUIT_EXTENSION="true";
    '';
  
    # https://github.com/clarete/forbiddenfruit/pull/47 required to switch to pytest
    checkPhase = ''
      find ./build -name '*.so' -exec mv {} tests/unit \;
      nosetests
  