Question

If I have a dictionary in Python, and I iterate through it once, and then again later, is the iteration order guaranteed to be preserved given that I didn’t insert, delete, or update any items in the dictionary? (But I might have done look-ups).

Answer 1

Here is what dict.items() documentation says:

dict.items() return a copy of the dictionary’s list of (key, value) pairs.

If items(), keys(), values(), iteritems(), iterkeys(), and itervalues() are called with no intervening modifications to the dictionary, the lists will directly correspond.

I think it’s reasonable to assume that item ordering won’t change if all you do is iteration.