lists.sort() with cmp

[snippsat]

cmp is is removed in Python 3.

The cmp() function should be treated as gone, and the __cmp__() special method is no longer supported.

So it was a bad idea,and key=somthing is better and works also fine in Python 2.7.

and I would prefer a way without lambda, if that's possible. I seem to remember that a function could be used?

You can import itemgetter to avoid lambda.
But lambda is really nice with sorting:

>>> lst = [('Tom', 'C', 10), ('Kent', 'A', 12), ('Jenny', 'B', 15)]
>>> sorted(lst, key=lambda tup: tup[1])
[('Kent', 'A', 12), ('Jenny', 'B', 15), ('Tom', 'C', 10)]

Sorting middle elements to A,B,C.
Sorting HOW TO