python.pkgs.asyncio: remove

> This version is only relevant for Python 3.3,
> which does not include asyncio in its stdlib.
We don't ship 3.3 anymore.

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

@@ -1,5 +1,5 @@
 { stdenv, buildPythonPackage, fetchPypi
-, isPy33, isPy27, isPyPy, python, pycares, typing, asyncio, trollius }:
+, isPy27, isPyPy, python, pycares, typing, trollius }:
 
 buildPythonPackage rec {
   pname = "aiodns";