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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 _init_glyph(self, plot, mapping, properties):
 """ Returns a Bokeh glyph object and optionally creates a colorbar. """

        ret = super(ColorbarPlot, self)._init_glyph(plot, mapping, properties)
        if self.colorbar:
            for k, v in list(self.handles.items()):
                if not k.endswith('color_mapper'):
                    continue
                self._draw_colorbar(plot, v, k[:-12])
        return ret