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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 pan_pan_cb(self, fitsimage, event):
 """Pan event in the pan window. Just pan the channel viewer. """

        chviewer = self.fv.getfocus_viewer()
        bd = chviewer.get_bindings()

        if hasattr(bd, 'pa_pan'):
            return bd.pa_pan(chviewer, event)

        return False