converting octal strings to unicode

[flamingivanova at gmail.com]

I have several ascii files that contain '\ooo' strings which represent
the octal value for a character. I want to convert these files to
unicode, and I came up with the following script. But it seems to me
that there must be a much simpler way to do it. Could someone more
experienced suggest some improvements?

I want to convert a file eg. containing:

hello \326du

with the unicode file containing:

hello Ödu


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#!/usr/bin/python

import re, string, sys

if len(sys.argv) > 1:
file = open(sys.argv[1],'r')
lines = file.readlines()
file.close()
else:
print "give a filename"
sys.exit()

def to_unichr(str):
oct = string.atoi(str.group(1),8)
return unichr(oct)

for line in lines:
line = string.rstrip(unicode(line,'Latin-1'))
if re.compile(r'\\\d\d\d').search(line):
line = re.sub(r'\\(\d\d\d)', to_unichr, line)
line = line.encode('utf-8')
print line

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