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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 add_port(self, port):
 """ Add a port object to the definition :param port: port definition :type port: PortDef """

        self.ports.append(port)
        if port.io_type not in self.port_seqs:
            self.port_seqs[port.io_type] = 0
        self.port_seqs[port.io_type] += 1
        port.sequence = self.port_seqs[port.io_type]
        return self