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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 start_tcp_server(self, port):
 """ Starts the TCP server using given port. :param port: Port. :type port: int :return: Method success. :rtype: bool """


        self.__tcp_server.port = port
        if not self.__tcp_server.online:
            if self.__tcp_server.start():
                self.__engine.notifications_manager.notify(
                    "{0} | TCP Server has started with '{1}' address on '{2}' port!".format(
                        self.__class__.__name__,
                        self.__address,
                        self.__port))
                return True
        else:
            self.__engine.notifications_manager.warnify(
                "{0} | TCP Server is already online!".format(self.__class__.__name__))
            return False