How to use the eventkit.ops.combine.AddableJoinOp.__init__ function in eventkit

def __init__(self, *sources):
        AddableJoinOp.__init__(self)
        self._qq = deque()
        self._source2cbs = defaultdict(list)  # map from source to callbacks
        self._set_sources(*sources)

def __init__(self, *sources):
        AddableJoinOp.__init__(self)
        self._source2cb = {}  # map from source to callback
        self._set_sources(*sources)

def __init__(self, *sources):
        AddableJoinOp.__init__(self)
        self._source2cb = {}  # map from source to callback
        self._active_source = None
        self._set_sources(*sources)