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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 get_iss_serial_no(self):
 """ Get serial number of USB-ISS module """

        self.write_data([self.ISS_CMD, self.ISS_SER_NUM])
        # Return 8 bytes serial number
        self.iss_sn = self.read_data(8)