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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 xpending(self, stream, group_name, start=None, stop=None, count=None, consumer=None):
 """Get information on pending messages for a stream Returned data will vary depending on the presence (or not) of the start/stop/count parameters. For more details see: https://redis.io/commands/xpending :raises ValueError: if the start/stop/count parameters are only partially specified """

        # Returns: total pel messages, min id, max id, count
        ssc = [start, stop, count]
        ssc_count = len([v for v in ssc if v is not None])
        if ssc_count != 3 and ssc_count != 0:
            raise ValueError(
                'Either specify non or all of the start/stop/count arguments'
            )
        if not any(ssc):
            ssc = []

        args = [stream, group_name] + ssc
        if consumer:
            args.append(consumer)
        return self.execute(b'XPENDING', *args)