sort Python list with two keys but only one in reverse order

Question

I was wondering what would be a Pythonic way of sorting a list of tuples by two keys whereby sorting with one (and only one) key would be in a reverse order and sorting with

Answer 1

One way could be to create a reversor class and use it to decorate the key in question. This class could be used to reverse any field that is comparable.

class reversor:
    def __init__(self, obj):
        self.obj = obj

    def __eq__(self, other):
        return other.obj == self.obj

    def __lt__(self, other):
        return other.obj < self.obj

Use it like so:

sortedList = sorted(myList, key=lambda(y): (y[0].lower(), reversor(y[1]))