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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 rgbmap_cb(self, rgbmap, channel):
 """ This method is called when the RGBMap is changed. We update the ColorBar to match. """

        if not self.gui_up:
            return
        fitsimage = channel.fitsimage
        if fitsimage != self.fv.getfocus_fitsimage():
            return False
        self.change_cbar(self.fv, channel)