def t(self):
        return u'%02d' % calendar.monthrange(self.data.year, self.data.month)[1]
Note that this is incredibly slow and painful.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/utils/dateformat.py/DateFormat.t--crossover with--dataset/ETHPy150Open zhemao/funktown/unittest.py/brutal_creation_test