.. method:: popitem()
- Remove and return an arbitrary ``(key, value)`` pair from the dictionary.
+ Remove and return a ``(key, value)`` pair from the dictionary.
+ Pairs are returned in :abbr:`LIFO (last-in, first-out)` order.
:meth:`popitem` is useful to destructively iterate over a dictionary, as
often used in set algorithms. If the dictionary is empty, calling
:meth:`popitem` raises a :exc:`KeyError`.
+ .. versionchanged:: 3.7
+
+ LIFO order is now guaranteed. In prior versions, :meth:`popitem` would
+ return an arbitrary key/value pair.
+
.. method:: setdefault(key[, default])
If *key* is in the dictionary, return its value. If not, insert *key*