Improve byte coding for multiple assignments.
Gives 30% speedup on "a,b=1,2" and 25% on "a,b,c=1,2,3".
diff --git a/Misc/NEWS b/Misc/NEWS
index 9f27fd7..f543eca 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
Core and builtins
-----------------
+- Optimized the byte coding for multiple assignments like "a,b=b,a" and
+ "a,b,c=1,2,3". Improves their speed by 25% to 30%.
+
- Limit the nested depth of a tuple for the second argument to isinstance()
and issubclass() to the recursion limit of the interpreter.
Fixes bug #858016 .