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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 ReadAllClientLabels(self):
 """Lists all client labels known to the system."""

    result = set()
    for labels_dict in itervalues(self.labels):
      for owner, names in iteritems(labels_dict):
        for name in names:
          result.add(rdf_objects.ClientLabel(owner=owner, name=name))

    return list(result)