> The JSON encoder for dictionaries preserves the order of the items in a dictionary

From what I can tell, the JSON encoder does nothing to preserve the order of the keys. Although the default option is to not modify the existing dictionary, the items() method returns the k,v pairs in a non-random arbitrary manner, which may not match the order the values were entered in. See https://docs.python.org/2/library/stdtypes.html#dict.items.