anchor.diff:  { lib, fetchPypi, buildPythonPackage, isPy3k, isPy35
   , mock
   , pysqlite
  -, pytest
  +, fetchpatch
  +, pytestCheckHook
   }:
   
   buildPythonPackage rec {
  
positive.code:   };
  
    checkInputs = [
      pytest
      mock
    ] ++ lib.optional (!isPy3k) pysqlite;
  
  
negative.code:     sed -e 's:--max-worker-restart=5::g' -i setup.cfg
    '';
  
    dontUseSetuptoolsCheck = true;
  
    disabledTests = lib.optionals isPy35 [ "exception_persistent_flush_py3k "];
  
    patches = [
      # Two patches for sqlite 3.30 compatibility.
      # https://github.com/sqlalchemy/sqlalchemy/pull/4921
      (fetchpatch {
        url = https://github.com/sqlalchemy/sqlalchemy/commit/8b35ba54ab31aab13a34c360a31d014da1f5c809.patch;
        sha256 = "065csr6pd7j1fjnv72wbz8s6xhydi5f161gj7nyqq86rxkh0nl0n";
      })
      (fetchpatch {
        url = https://github.com/sqlalchemy/sqlalchemy/commit/e18534a9045786efdaf4963515222838c62e0300.patch;
        sha256 = "0bwfwp5gmgg12qilvwdd2a5xi76bllzzapb23ybh1k34c5pla195";
      })
  
    ];
  
    meta = with lib; {
      homepage = http://www.sqlalchemy.org/;
  