<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def t(self):
    "Number of days in the given month; i.e. '28' to '31'"
    return u'%02d' % calendar.monthrange(self.data.year, self.data.month)[1]