dateutil

dateutil.rrule

import datetime;
import dateutil.rrule


date_1 = datetime.date(2014, 8, 25)
date_2 = datetime.date(2014, 9,  7)

for dt in dateutil.rrule.rrule(dateutil.rrule.DAILY, dtstart=date_1, until=date_2):
    print dt.strftime("%y-%m-%d")

dateutil.relativedelta

import datetime;
import dateutil;
import dateutil.relativedelta;

date_1 = datetime.date(2010, 04, 18)
date_2 = datetime.date(2010, 06, 22)

date_diff = dateutil.relativedelta.relativedelta(date_2, date_1)

print "Diff between ", date_1, " and ", date_2, " is: " , date_diff # relativedelta(months=+2, days=+4)

See also