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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def last_updated(self, since, queue=None):
 """ Obtains tickets changed after given date. :param since: Date as string in form '2011-02-24' :keyword queue: Queue where to search :returns: List of tickets with LastUpdated parameter later than *since* ordered in decreasing order by LastUpdated. Each tickets is dictionary, the same as in :py:meth:`~Rt.get_ticket`. """

        return self.search(Queue=queue, order='-LastUpdated', LastUpdatedBy__notexact=self.default_login, LastUpdated__gt=since)