import os

import hashlib

def get_file_md5(filename):

  if not os.path.isfile(filename):

    return

  md5 = hashlib.md5()

  f = file(filename,'rb')

  while True:

    b = f.read(8096)

    if not b:

      break

    md5.update(b)

  f.close()

  return md5.hexdigest()

然后我们打印下这几个文件的md5值

print 'file1   的md5:%s' % get_file_md5('file1.txt')

print 'file1_copy的md5:%s' % get_file_md5('file1_copy.txt')

print 'file2   的md5:%s' % get_file_md5('file2.txt')

import difflib

import sys

file1 = open('file1.txt', 'U').readlines()

file2 = open('file2.txt', 'U').readlines()

diff = difflib.ndiff(file1, file2)

sys.stdout.writelines(diff)