docs: 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