anchor.diff:  { lib, fetchFromGitHub, fetchpatch, python3 }:
  -python3.pkgs.buildPythonApplication rec {
  +
  +let
  +  python = python3.override {
  +    packageOverrides = self: super: {
  +      mautrix = super.mautrix.overridePythonAttrs (oldAttrs: rec {
  +        version = "0.16.3";
  +        src = oldAttrs.src.override {
  +          inherit (oldAttrs) pname;
  +          inherit version;
  +          sha256 = "sha256-OpHLh5pCzGooQ5yxAa0+85m/szAafV+l+OfipQcfLtU=";
  +        };
  +      });
  +    };
  +  };
  +
  +in python.pkgs.buildPythonApplication rec {
     pname = "heisenbridge";
     version = "1.13.1";
   
  
positive.code:     pyyaml
    ];
  
    checkInputs = with python3.pkgs; [
      pytestCheckHook
    ];
  
  
negative.code:     echo "${version}" > heisenbridge/version.txt
    '';
  
    propagatedBuildInputs = with python.pkgs; [
      aiohttp
      irc
      mautrix
  