python.pkgs.zipfile36: move expression

pkgs/development/python-modules/zipfile36/default.nix

···
+{ lib
+, buildPythonPackage
+, fetchPypi
+, python
+, isPy3k
+, pythonOlder
+}:
+
+buildPythonPackage rec {
+  pname = "zipfile36";
+  version = "0.1.3";
+  name = "${pname}-${version}";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "a78a8dddf4fa114f7fe73df76ffcce7538e23433b7a6a96c1c904023f122aead";
+  };
+
+  checkPhase = ''
+    ${python.interpreter} -m unittest test_zipfile.py
+  '';
+
+  # Only works with Python 3.x.
+  # Not supposed to be used with 3.6 and up.
+  disabled = !(isPy3k && (pythonOlder "3.6"));
+
+  meta = {
+    description = "Read and write ZIP files - backport of the zipfile module from Python 3.6";
+    homepage = https://gitlab.com/takluyver/zipfile36;
+    license = lib.licenses.psfl;
+    maintainer = lib.maintainers.fridh;
+  };
+}

pkgs/top-level/python-packages.nix

···
 
   zeroconf = callPackage ../development/python-modules/zeroconf { };
 
-  zipfile36 = buildPythonPackage rec {
-    pname = "zipfile36";
-    version = "0.1.3";
-    name = "${pname}-${version}";
-
-    src = pkgs.fetchurl {
-      url = "mirror://pypi/${builtins.substring 0 1 pname}/${pname}/${name}.tar.gz";
-      sha256 = "a78a8dddf4fa114f7fe73df76ffcce7538e23433b7a6a96c1c904023f122aead";
-    };
-
-    checkPhase = ''
-      ${python.interpreter} -m unittest test_zipfile.py
-    '';
-
-    # Only works with Python 3.x.
-    # Not supposed to be used with 3.6 and up.
-    disabled = !(isPy3k && (pythonOlder "3.6"));
-
-    meta = {
-      description = "Read and write ZIP files - backport of the zipfile module from Python 3.6";
-      homepage = https://gitlab.com/takluyver/zipfile36;
-      license = licenses.psfl;
-      maintainer = maintainers.fridh;
-    };
-  };
+  zipfile36 = callPackage ../development/python-modules/zipfile36 { };
 
   todoist = callPackage ../development/python-modules/todoist { };