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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 add_labelset(self, labelset):
 """ Add a set of labels to the plot. :param labelset: the set of labels to be added :type labelset: :class:`~aeneas.plotter.PlotLabelset` :raises: TypeError: if ``labelset`` is not an instance of :class:`~aeneas.plotter.PlotLabelset` """

        if not isinstance(labelset, PlotLabelset):
            self.log_exc(u"labelset must be an instance of PlotLabelset", None, True, TypeError)
        self.labelsets.append(labelset)
        self.log(u"Added labelset")