pythonPackages.request-cache: Move to own file

pkgs/development/python-modules/requests-cache/default.nix

@@ -0,0 +1,21 @@
+{ stdenv, buildPythonPackage, fetchPypi
+, mock, requests, six, urllib3 }:
+
+buildPythonPackage rec {
+  pname = "requests-cache";
+  version = "0.4.13";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "18jpyivnq5pjbkymk3i473rihpj2bgikafpha7xvr6w736hiqmpy";
+  };
+
+  buildInputs = [ mock ];
+  propagatedBuildInputs = [ requests six urllib3 ];
+
+  meta = with stdenv.lib; {
+    description = "Persistent cache for requests library";
+    homepage = https://pypi.python.org/pypi/requests-cache;
+    license = licenses.bsd3;
+  };
+}

pkgs/top-level/python-packages.nix

@@ -2057,25 +2057,7 @@ in {
 
   datashape = callPackage ../development/python-modules/datashape { };
 
-  requests-cache = buildPythonPackage (rec {
+  requests-cache = callPackage ../development/python-modules/requests-cache { };
-    name = "requests-cache-${version}";
-    version = "0.4.13";
-
-    src = pkgs.fetchurl {
-      url = "mirror://pypi/r/requests-cache/${name}.tar.gz";
-      sha256 = "18jpyivnq5pjbkymk3i473rihpj2bgikafpha7xvr6w736hiqmpy";
-    };
-
-    buildInputs = with self; [ mock ];
-
-    propagatedBuildInputs = with self; [ requests six urllib3 ];
-
-    meta = {
-      description = "Persistent cache for requests library";
-      homepage = https://pypi.python.org/pypi/requests-cache;
-      license = licenses.bsd3;
-    };
-  });
 
   requests-unixsocket = callPackage ../development/python-modules/requests-unixsocket {};