How to sort with lambda in Python

Question

In Python, I am trying to sort by date with lambda. I can\'t understand my error message. The message is:

() takes exactly 1 argument (2 given         


        

Answer 1

Use

a = sorted(a, key=lambda x: x.modified, reverse=True)
#             ^^^^

On Python 2.x, the sorted function takes its arguments in this order:

sorted(iterable, cmp=None, key=None, reverse=False)

so without the key=, the function you pass in will be considered a cmp function which takes 2 arguments.