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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 set_tcp_port(self, tcp_port):
 """ Defines the TCP port number. :type tcp_port: int :param tcp_port: The TCP port number. """

        if tcp_port is None:
            self.tcp_port = None
            return
        self.tcp_port = int(tcp_port)