human
Solve the following python programming problem given the following code:
@ extensionmethod (Observable) 
def ignore_elements(self) : 
    'Ignores all elements in an observable sequence leaving only the
    termination messages.

    Returns an empty observable {Observable} sequence that signals
    termination, successful or exceptional, of the source sequence.
    ' 
    source = self 
    def subscribe(observer) : 
        return source.subscribe (noop, observer.on_error, observer.on_completed) 
return AnonymousObservable (source) 

    
    

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

return AnonymousObservable (subscribe)