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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 GetLaunchedFlows(self, flow_type="outstanding"):
 """Returns the session IDs of all the flows we launched. Args: flow_type: The type of flows to fetch. Can be "all", "outstanding" or "finished". Returns: A list of flow URNs. """

    result = None
    all_clients = set(self.ListAllClients())
    finished_clients = set(self.ListFinishedClients())
    outstanding_clients = all_clients - finished_clients

    if flow_type == "all":
      result = all_clients
    elif flow_type == "finished":
      result = finished_clients
    elif flow_type == "outstanding":
      result = outstanding_clients

    # Now get the flows for all these clients.
    flows = aff4.FACTORY.MultiListChildren(
        [self.urn.Add(x.Basename()) for x in result])

    return [x[0] for _, x in flows]