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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 smsc(self, smscNumber):
 """ Set the default SMSC number to use when sending SMS messages """

        if smscNumber != self._smscNumber:
            if self.alive:
                self.write('AT+CSCA="{0}"'.format(smscNumber))
            self._smscNumber = smscNumber