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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 up(self, role, root_priority, root_times):
 """ A port is started in the state of LISTEN. """

        self.port_priority = root_priority
        self.port_times = root_times

        state = (PORT_STATE_LISTEN if self.config_enable
                 else PORT_STATE_DISABLE)
        self._change_role(role)
        self._change_status(state)