anchor.diff:  
     src = fetchPypi {
       inherit pname version;
  -    sha256 = "8e841d1bf3434da985cc5ef13e6f75c8981ced601fd70cc6bf33351b91562981";
  +    sha256 = "sha256-pSRtLmg6ly4hh6hxS1ws+BVsBkYp+amxqHPBcw2eJFo=";
     };
  +
  +  outputs = [ "out" "doc" ];
   
     nativeBuildInputs = [
       postgresql
  
positive.code: 
  buildPythonPackage rec {
    pname = "psycopg2";
    version = "2.9.3";
    outputs = [ "out" "doc" ];
  
    # Extension modules don't work well with PyPy. Use psycopg2cffi instead.
    # c.f. https://github.com/NixOS/nixpkgs/pull/104151#issuecomment-729750892
  
negative.code: 
    sphinxRoot = "doc/src";
  
    # Requires setting up a PostgreSQL database
    doCheck = false;
  
    pythonImportsCheck = [
      "psycopg2"
    ];
  
    meta = with lib; {
      description = "PostgreSQL database adapter for the Python programming language";
      homepage = "https://www.psycopg.org";
      license = with licenses; [ lgpl3Plus zpl20 ];
      maintainers = with maintainers; [ ];
    };
  }
  