[Python-3000] Default dict iterator should have been iteritems()

["Martin v. Löwis"]

> (assuming d[x] is  O(log n))

In Python, d[x] is typically considered to be O(1) (unlike in C++,
where it is O(log n)). Of course, with Python using a hashtable,
performance may decrease in the presence of collisions. In the
normal case, dict((x, d[x]) for x in d) will be O(n) in Python.

Regards,
Martin