'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.'

def GetLaunchedFlows(self, flow_type='outstanding'):

    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
    flows = aff4.FACTORY.MultiListChildren([self.urn.Add(x.Basename()) for x in result])
    return [x[0] for (_, x) in flows]
