anchor.diff:      owner = "dask";
       repo = pname;
       rev = version;
  -    sha256 = "08nvxj81cz9x92dh2gbmm4imkr8cfljfi2hxkballv2ygwcbzg8g";
  +    sha256 = "1irp6s577yyjvrvkg00hh1wnl8vrv7pbnbr09mk67z9y7s6xhiw3";
     };
   
     checkInputs = [
  
positive.code: 
  buildPythonPackage rec {
    pname = "dask";
    version = "2.22.0";
  
    disabled = pythonOlder "3.5";
  
  
negative.code: 
    meta = {
      description = "Minimal task scheduling abstraction";
      homepage = "https://dask.org/";
      changelog = "https://docs.dask.org/en/latest/changelog.html";
      license = lib.licenses.bsd3;
      maintainers = with lib.maintainers; [ fridh ];
    };
  