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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_cb(self, setting, value):
 """Handle callback related to changes in pan."""

        pan_x, pan_y = value[:2]

        self.logger.debug("pan set to %.2f,%.2f" % (pan_x, pan_y))
        self.redraw(whence=0)