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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 zGetUpdate(self):
 """Update the lens"""

        status,ret = -998, None
        ret = self._sendDDEcommand("GetUpdate")
        if ret != None:
            status = int(ret)  #Note: Zemax returns -1 if GetUpdate fails.
        return status