Better Look Before You Leap logic for reorder_keys.
Better Look Before You Leap logic for reorder_keys.

reorder_keys now checks the length of the iterable of keys passed in
against self._keys, making sure you don't change the number of members.
It also uses sets to make sure that the keys parameter contains exactly
the same keys as the _dict.

JustusW/BetterOrderedDict,therealfakemoot/collections2