#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys

inp_file = open(sys.argv[1])
out_file = open(sys.argv[2], "w")

for line in inp_file:
    line = line.strip()
    if line.endswith("mail.ru") or line.endswith("bk.ru"):
        out_file.write("%s\n" % line)

python filename.py input.txt output.txt