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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 SetAttributes(self, urn, attributes, to_delete, add_child_index=True, mutation_pool=None):
 """Sets the attributes in the data store."""


    attributes[AFF4Object.SchemaCls.LAST] = [
        rdfvalue.RDFDatetime.Now().SerializeToDataStore()
    ]
    to_delete.add(AFF4Object.SchemaCls.LAST)
    if mutation_pool:
      pool = mutation_pool
    else:
      pool = data_store.DB.GetMutationPool()

    pool.MultiSet(urn, attributes, replace=False, to_delete=to_delete)

    if add_child_index:
      self._UpdateChildIndex(urn, pool)
    if mutation_pool is None:
      pool.Flush()