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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 cmd_ppp(self, args):
        '''set ppp parameters and start link'''
        usage = "ppp <command|start|stop>"
        if len(args) == 0:
            print(usage)
            return
        if args[0] == "command":
            if len(args) == 1:
                print("ppp.command=%s" % " ".join(self.command))
            else:
                self.command = args[1:]
        elif args[0] == "start":
            self.start_ppp_link()
        elif args[0] == "stop":
            self.stop_ppp_link()
        elif args[0] == "status":
            self.console.writeln("%u packets %u bytes" % (self.packet_count, self.byte_count))