#!/usr/bin/env python

import mailbox, rfc822
import sys, os, string, re

LF = '\x0a'

def write_msg (fout, msg):
    fout.write (msg.unixfrom)
    for l in msg.headers:
        fout.write(l)
    fout.write(LF)
    fout.write(msg.fp.read())

def process_mailbox (mbox_in, mbox_out):
    f = open(mbox_in)
    fout = open(mbox_out, 'w')

    mb = mailbox.PortableUnixMailbox (f)

    found_ids = {}

    for msg in mb:
        id = msg.getheader('Message-ID')
        if found_ids.has_key(id):
            continue
        found_ids[id] = True

        write_msg (fout, msg)

    f.close()
    fout.close()

def main ():
    mbox_in = sys.argv[1]
    mbox_out = mbox_in + '.out'
    process_mailbox (mbox_in, mbox_out)

if __name__ == '__main__':
    main ()