human
Solve the following python programming problem given the following code:
@ extensionmethod (Observable) 
def multicast(self, subject = None, subject_selector = None, selector = None) : 
    'Multicasts the source sequence notifications through an instantiated
    subject into all uses of the sequence within a selector function. Each
    subscription to the resulting sequence causes a separate multicast
    invocation, exposing the sequence resulting from the selector function\'s
    invocation. For specializations with fixed subject types, see Publish,
    PublishLast, and Replay.

    Example:
    1 - res = source.multicast(observable)
    2 - res = source.multicast(subject_selector=lambda: Subject(),
                               selector=lambda x: x)

    Keyword arguments:
    subject_selector -- {Function} Factory function to create an
        intermediate subject through which the source sequence\'s elements
        will be multicast to the selector function.
    subject -- Subject {Subject} to push source elements into.
    selector -- {Function} [Optional] Optional selector function which can
        use the multicasted source sequence subject to the policies enforced
        by the created subject. Specified only if subject_selector" is a
        factory function.

    Returns an observable {Observable} sequence that contains the elements
    of a sequence produced by multicasting the source sequence within a
    selector function.
    ' 
    source = self 
    if subject_selector : 
        def subscribe(observer) : 
            connectable = source.multicast (subject = subject_selector ()) 
            return CompositeDisposable (selector (connectable).subscribe (observer), connectable.connect ()) 
return AnonymousObservable (subscribe) 
else : 
        return ConnectableObservable (source, subject_selector) 

    
    

    Fix the buggy line: return ConnectableObservable (source, subject_selector)
assistant
#Here is Python code to fix the buggy line: return ConnectableObservable (source, subject_selector)
.

return ConnectableObservable (source, subject)