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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 pending(self, start='-', stop='+', count=1000, consumer=None):
 """ List pending messages within the consumer group for this stream. :param start: start id (or '-' for oldest pending) :param stop: stop id (or '+' for newest pending) :param count: limit number of messages returned :param consumer: restrict message list to the given consumer :returns: A list containing status for each pending message. Each pending message returns [id, consumer, idle time, deliveries]. """

        return self.database.xpending_range(self.key, self.group, start, stop,
                                            count, consumer)