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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 unpack_close(self):
 """ Unpack a close message into a status code and a reason. If no payload is given, the code is None and the reason is an empty string. """

        if self.payload:
            code = struct.unpack('!H', str(self.payload[:2]))[0]
            reason = str(self.payload[2:])
        else:
            code = None
            reason = ''

        return code, reason