Sorting dates with python

Question

I have a list of strings like below.

>>> mylist = ["2013-09-07T11:23:43", "2013-09-05T15:14:12", "2013-10-13T22:06:22", "2013-11-16T23:01:34", "2013-12-22T23:11:54"]

I want to sort these as they are dates.

>>> mylist.sort()

This seems to work as I would like but will this always work with any date in this format?

>>> mylist
['2013-09-05T15:14:12', '2013-09-07T11:23:43', '2013-10-13T22:06:22', '2013-11-16T23:01:34', '2013-12-22T23:11:54']

Martijn Pieters · Accepted Answer · 2013-11-19 13:45:30Z

8

Yes, that works with any date in that format, because they are:

using the same length, zero-padded numbers
in the same order
ordered by most significant to least significant; year, month, day, hour, minute, second

This makes them lexicographically orderable, which is exactly the order sorting would apply.

answered Nov 19, 2013 at 13:45

Martijn Pieters

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