python - How to sort tuple twice -

for example,

a = [(4, 3), (6, 3), (2, 1), (3, 1)] 

how sort tuple twice without using itemgetter? want sort first key = a[1] , second key = a[0]. this,

a = [(6, 3), (4, 3), (3, 1), (2, 1)] 

just reverse sort:

sorted(a, reverse=true) 

for new list or

a.sorted(reverse=true) 

to sort list in-place.

tuples compared lexicographically, first first element, second in case of tie. sorting first second element, first, result in exactly same order if first sorted second element , sorted resulting list first:

>>> operator import itemgetter >>> = [(4, 3), (6, 3), (2, 1), (3, 1)] >>> sorted(a, key=itemgetter(1), reverse=true) [(4, 3), (6, 3), (2, 1), (3, 1)] >>> sorted(sorted(a, key=itemgetter(1), reverse=true), key=itemgetter(0), reverse=true) [(6, 3), (4, 3), (3, 1), (2, 1)] >>> sorted(a, reverse=true) [(6, 3), (4, 3), (3, 1), (2, 1)] 

if input has tuples more 2 elements elements must ignored, can still use itemgetter(), because supports multiple indices (at point returns tuple of values @ indices):

>>> itemgetter(0, 1)(a[0]) (4, 3) >>> sorted(a, key=itemgetter(0, 1), reverse=true) [(6, 3), (4, 3), (3, 1), (2, 1)]