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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_written_resolver(riak_object):
 """ A conflict-resolution function that resolves by selecting the most recently-modified sibling by timestamp. :param riak_object: an object-in-conflict that will be resolved :type riak_object: :class:`RiakObject <riak.riak_object.RiakObject>` """

    riak_object.siblings = [max(riak_object.siblings,
                                key=lambda x: x.last_modified), ]