以下脚本摘自笨学python，个人添加了备注
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1、脚本
from sys import argv
from os.path import exists
script,from_file,to_file = argv
print("Copy file %s to file %s" %(from_file,to_file))
#以读的方式打开from_file
in_file = open(from_file,"r")
#将in_file文档的内容读取出来
indata = in_file.read()
#将in_file文档的内容打印出来
print(indata)
print("the input file is %d bytes long" %len(indata))
print("Does the output file exists? %r" %exists(to_file))
print ("ready,hit RETURN to continue, CTRL-C to abort.")
#以读的方式打开to_file
out_file = open (to_file,‘w‘)
#将indata的内容写入out_file
out_file.write(indata)
#在写入后，再次以读的方式打开to_file
out_file = open(to_file,‘r‘)
#将out_file文档的内容读取出来
outdata = out_file.read()
#将out_file文档的内容打印出来
print(outdata)
out_file.close()
in_file.close()
print("Alright,all done.")
2、执行结果
3、01txt内容为：
