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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 GetAllClientLabels(token, include_catchall=False):
 """Get the set of all label names applied to all clients. Args: token: token to use when opening the index. include_catchall: If true, we include ALL_CLIENTS_LABEL in the results. Returns: set of label name strings, including the catchall "All" """

  labels_index = aff4.FACTORY.Create(
      standard.LabelSet.CLIENT_LABELS_URN,
      standard.LabelSet,
      mode="r",
      token=token)
  labels = set(labels_index.ListLabels())
  if include_catchall:
    labels.add(ALL_CLIENTS_LABEL)
  return labels