How to change time formats in python?

Question

How do i get the following list

 [datetime.date(2011, 4, 1), datetime.date(2011, 4, 8), datetime.date(2011, 4, 16), datetime.date(2011, 5, 21)]

as

['2011-04','2011-05']

It not only convert to string but remove dups

Answer 1

Convert the dates to strings using datetime.date.strftime.

dates = [date.strftime('%Y-%m') for date in dates]

You can remove duplicates by converting the list to a set and then back to a list.

dates = list(set(dates))

Then combine both methods to do it all in one step.

dates = list(set([date.strftime('%Y-%m') for date in dates]))

Answer 2

In [43]: import datetime

In [44]: dates=[datetime.date(2011, 4, 1), datetime.date(2011, 4, 8), datetime.date(2011, 4, 16), datetime.date(2011, 5, 21)]

In [45]: set([date.strftime('%Y-%m') for date in dates])
Out[45]: set(['2011-04', '2011-05'])