来位大神救救孩子吧，不会文件啊

#!/usr/bin/python3
# -*- coding:utf-8 -*-

import sys
infile = sys.argv[1]
outfile = sys.argv[2]
listin=[]
listout=[]
print(infile, type(infile))
print(outfile, type(outfile))

#读入
with open(infile, "rt") as in_file:
    text = in_file.read()
    listin.extend(text.split(" "))
print(listin)

#排序
listin.sort();
print(listin)

#去重
for i in listin:
    if i not in listout:
        listout.append(i)
print(listout)

with open(outfile, "wt") as out_file:
    out_file.write(" ".join(listout))

in.txt 内容

aa bb cc dd aa ava ssd dws nn cc dd cc aa ee

运行结果

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