def last_quarter():
        """ Return start and end date of this quarter. """
        since, until = Date.this_quarter()
        since = since.date - delta(months=3)
        until = until.date - delta(months=3)
        return Date(since), Date(until)
def last_quarter ( ) : since , until = Date . this_quarter ( ) since = since . date - delta ( months = 3 ) until = until . date - delta ( months = 3 ) return Date ( since ) , Date ( until )
Return start and end date of this quarter.