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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 _fontsize(self, key, label='fontsize', common=True):
 """ Converts integer fontsizes to a string specifying fontsize in pt. """

        size = super(BokehPlot, self)._fontsize(key, label, common)
        return {k: v if isinstance(v, basestring) else '%spt' % v
                for k, v in size.items()}