another nix python packaging example

02-add-entrypoints.patch

diff --git a/setup.py b/setup.py
index a15336d..307fb56 100644
--- a/setup.py
+++ b/setup.py
@@ -60,6 +60,9 @@ setuptools.setup(
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
     ],
+    entry_points={"console_scripts": [
+        "mautrix-hangouts = mautrix_hangouts.__main__:main"
+    ]},
     package_data={"mautrix_hangouts": [
         "web/static/*.png", "web/static/*.css", "web/static/*.html", "web/static/*.js",
         "example-config.yaml"

default.nix

{ pkgs ? import <nixpkgs> {}
}:

(import ./setup.nix {}).targetPython.pkgs.mautrix-hangouts

python-packages.nix

# Generated by pip2nix 0.8.0.dev1
# See https://github.com/nix-community/pip2nix

{ pkgs, fetchurl, fetchgit, fetchhg }:

self: super: {
  "ConfigArgParse" = super.buildPythonPackage rec {
    pname = "ConfigArgParse";
    version = "1.2.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/bb/79/3045743bb26ca2e44a1d317c37395462bfed82dbbd38e69a3280b63696ce/ConfigArgParse-1.2.3.tar.gz";
      sha256 = "1p1pzpf5qpf80bfxsx1mbw9blyhhypjvhl3i60pbmhfmhvlpplgd";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "Mako" = super.buildPythonPackage rec {
    pname = "Mako";
    version = "1.1.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/a6/37/0e706200d22172eb8fa17d68a7ae22dec7631a0a92266634fb518a88a5b2/Mako-1.1.3-py2.py3-none-any.whl";
      sha256 = "1adnqx2q5mnjrhj675vfjhl80xdry46y5nbbhxy79w2giqjrlwlk";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."MarkupSafe"
    ];
  };
  "MarkupSafe" = super.buildPythonPackage rec {
    pname = "MarkupSafe";
    version = "1.1.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/b9/2e/64db92e53b86efccfaea71321f597fa2e1b2bd3853d8ce658568f7a13094/MarkupSafe-1.1.1.tar.gz";
      sha256 = "0sqipg4fk7xbixqd8kq6rlkxj664d157bdwbh93farcphf92x1r9";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "MechanicalSoup" = super.buildPythonPackage rec {
    pname = "MechanicalSoup";
    version = "0.12.0";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/0b/fe/4f871ec3379080c5979815bfec3266871e555eebf4879f551a7e5dee4766/MechanicalSoup-0.12.0-py2.py3-none-any.whl";
      sha256 = "0f2j1pi7wq0f42imyaik7szfcm3qd7s3sivs2gyxlkszjyq81pfd";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."beautifulsoup4"
      self."lxml"
      self."requests"
      self."six"
    ];
  };
  "ReParser" = super.buildPythonPackage rec {
    pname = "ReParser";
    version = "1.4.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/a7/eb/8bd06ddaeb3d5963abb0e2e2f14f2fa975b32fafe198254bfb4106ed9415/ReParser-1.4.3.tar.gz";
      sha256 = "0nniqb69xr0fv7ydlmrr877wyyjb61nlayka7xr08vlxl9caz776";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "SQLAlchemy" = super.buildPythonPackage rec {
    pname = "SQLAlchemy";
    version = "1.3.20";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/69/ef/6d18860e18db68b8f25e0d268635f2f8cefa7a1cbf6d9d9f90214555a364/SQLAlchemy-1.3.20.tar.gz";
      sha256 = "18b9am7bsqc4nj3d2h5r93i002apczxfvpfpcqbd6f0385zmrwnj";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "aiohttp" = super.buildPythonPackage rec {
    pname = "aiohttp";
    version = "3.6.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/9d/6c/429faa2d2f73973189ca0cfe141ff703417a5eebe18d78e6b25b70db0a34/aiohttp-3.6.3.tar.gz";
      sha256 = "0i9n7h8n06m2d8ryqyk4fv1si1m44ibq7blbfaxq46vx7jydg339";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."async-timeout"
      self."attrs"
      self."chardet"
      self."multidict"
      self."yarl"
    ];
  };
  "alembic" = super.buildPythonPackage rec {
    pname = "alembic";
    version = "1.4.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/12/aa/c261dfd7f4ba6ce4701846a2689a46e2a172e012171de4378fc2926e3bf0/alembic-1.4.3-py2.py3-none-any.whl";
      sha256 = "0760f83chg376lcdc6fyfyq1zdam5h4zl6h4cnciggcnlwmfs0jf";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."Mako"
      self."SQLAlchemy"
      self."python-dateutil"
      self."python-editor"
    ];
  };
  "appdirs" = super.buildPythonPackage rec {
    pname = "appdirs";
    version = "1.4.4";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/3b/00/2344469e2084fb287c2e0b57b72910309874c3245463acd6cf5e3db69324/appdirs-1.4.4-py2.py3-none-any.whl";
      sha256 = "0a5ib82s2335nhvq5rjh8hkimrwyw43xnshn3ds8lccrdg6xlhd8";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "async-timeout" = super.buildPythonPackage rec {
    pname = "async-timeout";
    version = "3.0.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/e1/1e/5a4441be21b0726c4464f3f23c8b19628372f606755a9d2e46c187e65ec4/async_timeout-3.0.1-py3-none-any.whl";
      sha256 = "18wy5w0wk37ikx9n5yc8s9746bgqz3wdddbc1d6jfz98glcwm4a2";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "attrs" = super.buildPythonPackage rec {
    pname = "attrs";
    version = "20.2.0";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/14/df/479736ae1ef59842f512548bacefad1abed705e400212acba43f9b0fa556/attrs-20.2.0-py2.py3-none-any.whl";
      sha256 = "1p2mwqh0sykp2dm8h86d3b100xs0l0pzjgymh8p1axn9vx3zrrzw";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "beautifulsoup4" = super.buildPythonPackage rec {
    pname = "beautifulsoup4";
    version = "4.9.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/d1/41/e6495bd7d3781cee623ce23ea6ac73282a373088fcd0ddc809a047b18eae/beautifulsoup4-4.9.3-py3-none-any.whl";
      sha256 = "0rmn9z026in04c2y12x3xsdfczgyjbssh3g02yzq5v1l3q1pxx7z";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."soupsieve"
    ];
  };
  "certifi" = super.buildPythonPackage rec {
    pname = "certifi";
    version = "2020.6.20";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/5e/c4/6c4fe722df5343c33226f0b4e0bb042e4dc13483228b4718baf286f86d87/certifi-2020.6.20-py2.py3-none-any.whl";
      sha256 = "0hgw963hnmp907cpbsv81x19zn84xywzzkjcnfyibfih3ygq3h4g";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "chardet" = super.buildPythonPackage rec {
    pname = "chardet";
    version = "3.0.4";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/bc/a9/01ffebfb562e4274b6487b4bb1ddec7ca55ec7510b22e4c51f14098443b8/chardet-3.0.4-py2.py3-none-any.whl";
      sha256 = "14b621614q2lw7ik2igdv4qdbblqgdsiglgl5fhf1l5fmvy3ycpw";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "commonmark" = super.buildPythonPackage rec {
    pname = "commonmark";
    version = "0.9.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/b1/92/dfd892312d822f36c55366118b95d914e5f16de11044a27cf10a7d71bbbf/commonmark-0.9.1-py2.py3-none-any.whl";
      sha256 = "1nbgsvb73ad93cjzjdggkpp4zizvxay3q6ms23j3vy4h4p4khbys";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "hangups" = super.buildPythonPackage rec {
    pname = "hangups";
    version = "0.4.12";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/ea/e7/2e59d47d8d3071b8b92b5f633e600ebe9d8210f566c895e988d88161e9a1/hangups-0.4.12.tar.gz";
      sha256 = "06vhn5mx2h4b1rgwwhqbi1kx1mwddd55ygkc5jfaqpwisbmfv9hs";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."ConfigArgParse"
      self."MechanicalSoup"
      self."ReParser"
      self."aiohttp"
      self."appdirs"
      self."async-timeout"
      self."protobuf"
      self."readlike"
      self."requests"
      self."urwid"
    ];
  };
  "idna" = super.buildPythonPackage rec {
    pname = "idna";
    version = "2.10";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/a2/38/928ddce2273eaa564f6f50de919327bf3a00f091b5baba8dfa9460f3a8a8/idna-2.10-py2.py3-none-any.whl";
      sha256 = "1h280sli58v5dapmf79rnnqdrrk0xjn8vi3pxppknllv3r5q0zdr";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "lxml" = super.buildPythonPackage rec {
    pname = "lxml";
    version = "4.6.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/c5/2f/a0d8aa3eee6d53d5723d89e1fc32eee11e76801b424e30b55c7aa6302b01/lxml-4.6.1.tar.gz";
      sha256 = "0rxkvjx6ffp8v3y6hdmqnsrfz3javr6a532sxhv1z7b37glv4ln1";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "mautrix" = super.buildPythonPackage rec {
    pname = "mautrix";
    version = "0.7.13";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/df/cc/f04f4b521d9697fb71e4687354125f0e74c4510867785724ffcf1a2939bf/mautrix-0.7.13-py3-none-any.whl";
      sha256 = "14v75pamz0g9qx9w9qcqiqpidyk2m1agm23rbbd792fazqz4znfk";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."aiohttp"
      self."attrs"
    ];
  };
  "mautrix-hangouts" = super.buildPythonPackage rec {
    pname = "mautrix-hangouts";
    version = "0.1.3+dev.f83d69fe";
    src = fetchgit {
      url = "git://github.com/rihardsk/mautrix-hangouts.git";
      rev = "f83d69fe43370207dfba22bba38ff2f421fa2971";
      sha256 = "06w5mf8d6dwq59w74pk74iffv08fxpk21b0n5amq8ln2cq32bxfb";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."SQLAlchemy"
      self."aiohttp"
      self."alembic"
      self."commonmark"
      self."hangups"
      self."mautrix"
      self."python-magic"
      self."ruamel.yaml"
    ];
  };
  "multidict" = super.buildPythonPackage rec {
    pname = "multidict";
    version = "4.7.6";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/65/d4/fabdcc5ee4451c8a8e177e27ddfd131a53a82ecc5a3b68468b7e9f8d70b4/multidict-4.7.6.tar.gz";
      sha256 = "0c0lp75p5z6zmpsy8ar099kj6kggi0yq4kld99y1w0i9wmspmdzv";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "protobuf" = super.buildPythonPackage rec {
    pname = "protobuf";
    version = "3.13.0";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/25/ef/8f36bc7e4c3dcad241a9e7a51520d30712a7abc034343bed841ff4ea3289/protobuf-3.13.0.tar.gz";
      sha256 = "1dbx74p0w2vx5qg2ifmf9h4v45bpw0a5ik20c1h8zx9bpg4f10ka";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."setuptools"
      self."six"
    ];
  };
  "python-dateutil" = super.buildPythonPackage rec {
    pname = "python-dateutil";
    version = "2.8.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/d4/70/d60450c3dd48ef87586924207ae8907090de0b306af2bce5d134d78615cb/python_dateutil-2.8.1-py2.py3-none-any.whl";
      sha256 = "0answacgnckybm5iyfnaqsgval3mdbpak4i6fsbi2vv8x8qkzfvm";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."six"
    ];
  };
  "python-editor" = super.buildPythonPackage rec {
    pname = "python-editor";
    version = "1.0.4";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/c6/d3/201fc3abe391bbae6606e6f1d598c15d367033332bd54352b12f35513717/python_editor-1.0.4-py3-none-any.whl";
      sha256 = "0z9nr2npc0ghk0jh436qirhk082vq9fjs9g17r6a2lmdm1hfixhv";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "python-magic" = super.buildPythonPackage rec {
    pname = "python-magic";
    version = "0.4.18";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/59/77/c76dc35249df428ce2c38a3196e2b2e8f9d2f847a8ca1d4d7a3973c28601/python_magic-0.4.18-py2.py3-none-any.whl";
      sha256 = "0mbk41rciqq5qd6aznvf6yqzb8hvhwgbjgkxxg8lg449r29zlvim";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "readlike" = super.buildPythonPackage rec {
    pname = "readlike";
    version = "0.1.3";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/71/02/d639167c3ed84b9c3040bc99ed97be67796b53635f0c4f23392918428324/readlike-0.1.3-py3-none-any.whl";
      sha256 = "0096zqa3nmn3zyi5yfjkzsscpy556zdsv2yqhd41gp5sqyd1fym8";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "requests" = super.buildPythonPackage rec {
    pname = "requests";
    version = "2.24.0";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/45/1e/0c169c6a5381e241ba7404532c16a21d86ab872c9bed8bdcd4c423954103/requests-2.24.0-py2.py3-none-any.whl";
      sha256 = "165qrd22rm0fp23kzfdc6qy12jv0fm7j4jbhzi394fs4m6acqxgy";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."certifi"
      self."chardet"
      self."idna"
      self."urllib3"
    ];
  };
  "ruamel.yaml" = super.buildPythonPackage rec {
    pname = "ruamel.yaml";
    version = "0.16.12";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/7e/39/186f14f3836ac5d2a6a042c8de69988770e8b9abb537610edc429e4914aa/ruamel.yaml-0.16.12-py2.py3-none-any.whl";
      sha256 = "19a0ccwafwzahx2a0ch2xrpb9xpdfw195rwr9vjf81pal1q98aq1";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."ruamel.yaml.clib"
    ];
  };
  "ruamel.yaml.clib" = super.buildPythonPackage rec {
    pname = "ruamel.yaml.clib";
    version = "0.2.2";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/fa/a1/f9c009a633fce3609e314294c7963abe64934d972abea257dce16a15666f/ruamel.yaml.clib-0.2.2.tar.gz";
      sha256 = "19vbh07cmn6jchqpcfpvldb9rcb05bfbq5fpqj84jvv7mycbs91d";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "six" = super.buildPythonPackage rec {
    pname = "six";
    version = "1.15.0";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/ee/ff/48bde5c0f013094d729fe4b0316ba2a24774b3ff1c52d924a8a4cb04078a/six-1.15.0-py2.py3-none-any.whl";
      sha256 = "1vaw9aqdsbg84s20yqmg24k5kcq65dpxg4bldpzkijmspgfbwx4b";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "soupsieve" = super.buildPythonPackage rec {
    pname = "soupsieve";
    version = "2.0.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/6f/8f/457f4a5390eeae1cc3aeab89deb7724c965be841ffca6cfca9197482e470/soupsieve-2.0.1-py3-none-any.whl";
      sha256 = "0mfcbvcs00p9id94fpbjy088da3hg3gr76rh8v9x6wdk5ajfwd0n";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "urllib3" = super.buildPythonPackage rec {
    pname = "urllib3";
    version = "1.25.11";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/56/aa/4ef5aa67a9a62505db124a5cb5262332d1d4153462eb8fd89c9fa41e5d92/urllib3-1.25.11-py2.py3-none-any.whl";
      sha256 = "0pnxjyc33d162wrxmk285av9x44h9sqpzzhbzl7gmzpk9fz1ycpm";
    };
    format = "wheel";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "urwid" = super.buildPythonPackage rec {
    pname = "urwid";
    version = "2.1.2";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/94/3f/e3010f4a11c08a5690540f7ebd0b0d251cc8a456895b7e49be201f73540c/urwid-2.1.2.tar.gz";
      sha256 = "1bky2bra6673xx8jy0826znw6cmxs89wcwwzda8d025j3jffx2sq";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [];
  };
  "yarl" = super.buildPythonPackage rec {
    pname = "yarl";
    version = "1.5.1";
    src = fetchurl {
      url = "https://files.pythonhosted.org/packages/ac/dd/59768bb3fa08e8b23e91575bca3ff8d2edbfbceebec8c59eaa24c4215791/yarl-1.5.1.tar.gz";
      sha256 = "1mn3avw5hnx31j03f6z0qx6q0glaw18saph40mqx9wwlyfspab62";
    };
    format = "setuptools";
    doCheck = false;
    buildInputs = [];
    checkInputs = [];
    nativeBuildInputs = [];
    propagatedBuildInputs = [
      self."idna"
      self."multidict"
    ];
  };
}

setup.nix

{ pkgs ? import (fetchTarball {  # NixOS 20.09
    url = "https://github.com/NixOS/nixpkgs/archive/cd63096d6d887d689543a0b97743d28995bc9bc3.tar.gz";
    sha256 = "1wg61h4gndm3vcprdcg7rc4s1v3jkm5xd7lw8r2f67w502y94gcy";
  }) { config = { allowBroken = true; }; }
, python ? "python38"
, pythonPackages ? builtins.getAttr (python + "Packages") pkgs
, requirements ?  ./. + "/python-packages.nix"
}:

with builtins;
with pkgs;
with pkgs.lib;

let

  # Load generated requirements
  requirementsFunc = import requirements {
    inherit pkgs;
    inherit (builtins) fetchurl;
    inherit (pkgs) fetchgit fetchhg;
  };

  # List package names in requirements
  requirementsNames = attrNames (requirementsFunc {} {});

  # Return base name from python drv name or name when not python drv
  pythonNameOrName = drv:
    if hasAttr "overridePythonAttrs" drv then drv.pname else drv.name;

  # Merge named input list from nixpkgs drv with input list from requirements drv
  mergedInputs = old: new: inputsName: self: super:
    (attrByPath [ inputsName ] [] new) ++ map
    (x: attrByPath [ (pythonNameOrName x) ] x self)
    (filter (x: !isNull x) (attrByPath [ inputsName ] [] old));

  # Merge package drv from nixpkgs drv with requirements drv
  mergedPackage = old: new: self: super:
    if isString new.src
       && !isNull (match ".*\.whl" new.src)  # do not merge build inputs for wheels
       && new.pname != "wheel"               # ...
    then new.overridePythonAttrs(old: rec {
      propagatedBuildInputs =
        mergedInputs old new "propagatedBuildInputs" self super;
    })
    else old.overridePythonAttrs(old: rec {
      inherit (new) pname version src;
      name = "${pname}-${version}";
      checkInputs =
        mergedInputs old new "checkInputs" self super;
      buildInputs =
        mergedInputs old new "buildInputs" self super;
      nativeBuildInputs =
        mergedInputs old new "nativeBuildInputs" self super;
      propagatedBuildInputs =
        mergedInputs old new "propagatedBuildInputs" self super;
      doCheck = false;
    });

  # Build python with manual aliases for naming differences between world and nix
  buildPython = (pythonPackages.python.override {
    packageOverrides = self: super:
      listToAttrs (map (name: {
        name = name; value = getAttr (getAttr name aliases) super;
      }) (filter (x: hasAttr (getAttr x aliases) super) (attrNames aliases)));
  });

  # Build target python with all generated & customized requirements
  targetPython = (buildPython.override {
    packageOverrides = self: super:
      # 1) Merge packages already in pythonPackages
      let super_ = (requirementsFunc self buildPython.pkgs);  # from requirements
          results = (listToAttrs (map (name: let new = getAttr name super_; in {
        inherit name;
        value = mergedPackage (getAttr name buildPython.pkgs) new self super_;
      })
      (filter (name: hasAttr "overridePythonAttrs"
                     (if (tryEval (attrByPath [ name ] {} buildPython.pkgs)).success
                      then (attrByPath [ name ] {} buildPython.pkgs) else {}))
       requirementsNames)))
      // # 2) with packages only in requirements or disabled in nixpkgs
      (listToAttrs (map (name: { inherit name; value = (getAttr name super_); })
      (filter (name: (! ((hasAttr name buildPython.pkgs) &&
                         (tryEval (getAttr name buildPython.pkgs)).success)))
       requirementsNames)));
      in # 3) finally, apply overrides (with aliased drvs mapped back)
      (let final = (super // (results //
        (listToAttrs (map (name: {
          name = getAttr name aliases; value = getAttr name results;
        }) (filter (x: hasAttr x results) (attrNames aliases))))
      )); in (final // (overrides self final)));
    self = buildPython;
  });

  # Helper to always return a list
  asList = name: attrs:
    if hasAttr name attrs then
      let candidate = getAttr name attrs; in
      if isList candidate then candidate else []
    else [];

  # Alias packages with different names in requirements and in nixpkgs
  aliases = {
  };

  # Final overrides to fix issues all the magic above cannot fix automatically
  overrides = self: super: {
    "protobuf" = super."protobuf".overridePythonAttrs(old: {
      prePatch = "";
    });
    "mautrix-hangouts" = super."mautrix-hangouts".overridePythonAttrs(old: {
      patches = [ ./02-add-entrypoints.patch ];
    });
    "six" = buildPython.pkgs."six";
    "python-dateutil" = buildPython.pkgs."python-dateutil";
    "python-magic" = buildPython.pkgs."python_magic";
  };

in rec {

  inherit buildPython targetPython;

  python = targetPython.withPackages(ps: map (name: getAttr name ps) requirementsNames);

  env = pkgs.buildEnv {
    name = "env";
    paths = [
      python
    ];
  };

  shell = pkgs.mkShell {
    buildInputs = [
      python
    ];
  };

}

shell.nix

{ pkgs ? import <nixpkgs> {}
}:

pkgs.mkShell {
  buildInputs = [
    (import ./setup.nix {}).python
  ];
}