diff -r 62438d1b11c7 Lib/_collections_abc.py
--- a/Lib/_collections_abc.py	Fri May 02 23:26:03 2014 +0200
+++ b/Lib/_collections_abc.py	Fri May 02 20:13:05 2014 -0400
@@ -194,10 +194,7 @@
             return NotImplemented
         if len(self) > len(other):
             return False
-        for elem in self:
-            if elem not in other:
-                return False
-        return True
+        return all(elem in other for elem in self)
 
     def __lt__(self, other):
         if not isinstance(other, Set):
@@ -219,9 +216,6 @@
             return NotImplemented
         return len(self) == len(other) and self.__le__(other)
 
-    def __ne__(self, other):
-        return not (self == other)
-
     @classmethod
     def _from_iterable(cls, it):
         '''Construct an instance of the class from any iterable input.
@@ -238,10 +232,7 @@
 
     def isdisjoint(self, other):
         'Return True if two sets have a null intersection.'
-        for value in other:
-            if value in self:
-                return False
-        return True
+        return all(value not in self for value in other)
 
     def __or__(self, other):
         if not isinstance(other, Iterable):
@@ -432,14 +423,13 @@
             return NotImplemented
         return dict(self.items()) == dict(other.items())
 
-    def __ne__(self, other):
-        return not (self == other)
-
 Mapping.register(mappingproxy)
 
 
 class MappingView(Sized):
 
+    __slots__ = '_mapping',
+
     def __init__(self, mapping):
         self._mapping = mapping
 
@@ -452,6 +442,8 @@
 
 class KeysView(MappingView, Set):
 
+    __slots__ = ()
+
     @classmethod
     def _from_iterable(self, it):
         return set(it)
@@ -467,6 +459,8 @@
 
 class ItemsView(MappingView, Set):
 
+    __slots__ = ()
+
     @classmethod
     def _from_iterable(self, it):
         return set(it)
@@ -489,11 +483,10 @@
 
 class ValuesView(MappingView):
 
+    __slots__ = ()
+
     def __contains__(self, value):
-        for key in self._mapping:
-            if value == self._mapping[key]:
-                return True
-        return False
+        return any(v == value for v in self)
 
     def __iter__(self):
         for key in self._mapping:
@@ -614,20 +607,11 @@
         raise IndexError
 
     def __iter__(self):
-        i = 0
-        try:
-            while True:
-                v = self[i]
-                yield v
-                i += 1
-        except IndexError:
-            return
+        for i in range(len(self)):
+            yield self[i]
 
     def __contains__(self, value):
-        for v in self:
-            if v == value:
-                return True
-        return False
+        return any(v == value for v in self)
 
     def __reversed__(self):
         for i in reversed(range(len(self))):