asyncio: remove unused imports and unused variables noticed by pyflakes
diff --git a/Lib/selectors.py b/Lib/selectors.py
index a5465e2..9be9225 100644
--- a/Lib/selectors.py
+++ b/Lib/selectors.py
@@ -5,9 +5,8 @@
 """
 
 
-from abc import ABCMeta, abstractmethod, abstractproperty
+from abc import ABCMeta, abstractmethod
 from collections import namedtuple, Mapping
-import functools
 import math
 import select
 import sys