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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 deleteObserver(self, observer):
 """Remove an observer."""

        Observable.deleteObserver(self, observer)
        # If self.startOnDemand is True, the reader monitoring
        # thread is stopped when there are no more observers.
        if self.startOnDemand:
            if 0 == self.countObservers():
                self.rmthread.stop()
                del self.rmthread
                self.rmthread = None