I am using Python 2.7.5 @ Mac OS X 10.9.3 with 8GB memory and 1.7GHz Core i5. I have tested time consumption as below.
d = {i:i*2 for i in xrange(10**7*3)} #WARN
Using for k,v in d.iteritems() with more descriptive names can make the code in the loop suite easier to read.
for k,v in d.iteritems()