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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 empty(self, duration):
        '''Create an empty jams.Annotation for this task.

        This method should be overridden by derived classes.

        Parameters
        ----------
        duration : int >= 0
            Duration of the annotation
        '''
        return jams.Annotation(namespace=self.namespace, time=0, duration=0)