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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 qpop_back(self, name, size=1):
 """ Remove and return the last ``size`` item of the list ``name`` Like **Redis.RPOP** :param string name: the queue name :param int size: the length of result :return: the list of pop elements :rtype: list """

        size = get_positive_integer("size", size)
        return self.execute_command('qpop_back', name, size)