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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 do_processlist(self, arg):
 """ pl - show the processes being debugged processlist - show the processes being debugged """

        if self.cmdprefix:
            raise CmdError("prefix not allowed")
        if arg:
            raise CmdError("too many arguments")
        system   = self.debug.system
        pid_list = self.debug.get_debugee_pids()
        if pid_list:
            print("Process ID   File name")
            for pid in pid_list:
                if   pid == 0:
                    filename = "System Idle Process"
                elif pid == 4:
                    filename = "System"
                else:
                    filename = system.get_process(pid).get_filename()
                    filename = PathOperations.pathname_to_filename(filename)
                print("%-12d %s" % (pid, filename))