python.pkgs: several maintenance updates

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

···
 buildPythonPackage rec {
   pname = "channels";
   name = "${pname}-${version}";
-  version = "1.1.5";
+  version = "1.1.6";
 
   src = fetchurl {
     url = "mirror://pypi/c/channels/${name}.tar.gz";
-    sha256 = "a9005bcb6104d26a7f93d9cf012bcf6765a0ff444a449ac68d6e1f16721f8ed3";
+    sha256 = "44ab9a1f610ecc9ac25d5f90e7a44f49b18de28a05a26fe34e935af257f1eefe";
   };
 
   # Files are missing in the distribution

pkgs/development/python-modules/django_guardian.nix

···
 buildPythonPackage rec {
   pname = "django-guardian";
   name = "${pname}-${version}";
-  version = "1.4.8";
+  version = "1.4.9";
 
   src = fetchurl {
     url = "mirror://pypi/d/django-guardian/${name}.tar.gz";
-    sha256 = "039mfx47c05vl6vlld0ahyq37z7m5g68vqc38pj8iic5ysr98drm";
+    sha256 = "c3c0ab257c9d94ce154b9ee32994e3cff8b350c384040705514e14a9fb7c8191";
   };
 
   buildInputs = [ pytest pytestrunner pytest-django django_environ mock setuptools_scm ];

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

···
 
 buildPythonPackage rec {
   pname = "dogpile.cache";
-  version = "0.6.3";
+  version = "0.6.4";
   name = "${pname}-${version}";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "e9747f5e31f8dea1b80d6204358885f943f69e53574d88005438ca3651c44553";
+    sha256 = "a73aa3049cd88d7ec57a1c2e8946abdf4f14188d429c1023943fcc55c4568da1";
   };
 
   # Disable concurrency tests that often fail,