anchor.diff:  
       src = pkgs.fetchurl {
         url = "https://pypi.python.org/packages/source/d/devpi-common/devpi-common-${version}.tar.gz";
  -      md5 = "3739af0f59151d1aaa67035fec8f97c6";
  +      sha256 = "a059c4099002d4af8f3ccfc8a9f4bf133b20ea404049b21a31fc1003e1d79452";
       };
   
       propagatedBuildInputs = [ self.requests2 self.py ];
  
positive.code: 
      src = pkgs.fetchurl {
        url = "http://pypi.pediapress.com/packages/mirror/${name}.zip";
        md5 = "36193837359204d3337b297ba0f20bc8";
      };
  
      meta = {
  
negative.code: 
      src = pkgs.fetchurl {
        url = "http://pypi.python.org/packages/source/i/influxdb/${name}.tar.gz";
        sha256 = "6b5ea154454b86d14f2a3960d180e666ba9863da964032dacf2b50628e774a33";
      };
  
      # ImportError: No module named tests
  