[crazyant@localhost PythonMd5]$ more sample_file 
www.crazyant.net
www.51projob.com
[crazyant@localhost PythonMd5]$ md5sum sample_file > sample_file.md5file
[crazyant@localhost PythonMd5]$ more sample_file.md5file 
311d384505e3622ccf85d88930e2b0a0 sample_file
[crazyant@localhost PythonMd5]$ md5sum -c sample_file.md5file 
sample_file: OK

# -*- encoding:utf-8 -*-
from hashlib import md5
import os
 
def generate_file_md5value(fpath):
 '''以文件路径作为参数，返回对文件md5后的值
 '''
 m = md5()
 # 需要使用二进制格式读取文件内容
 a_file = open(fpath, 'rb') 
 m.update(a_file.read())
 a_file.close()
 return m.hexdigest()
 
def generate_file_md5sumFile(fpath):
 fname = os.path.basename(fpath)
 fpath_md5 = "%s.md5" % fpath
 fout = open(fpath_md5, "w")
 fout.write("%s %s\n" % (generate_file_md5value(fpath), fname.strip()))
 print "generate success, fpath:%s" % fpath_md5
 fout.flush()
 fout.close()
 
if __name__ == "__main__":
 fpath = "/home/users/workbench/PythonMd5/sample_file"
 # 测试一：以文件路径作为参数，获得md5后的字符串
 print generate_file_md5value(fpath)
 
 # 测试二：生成和linux命令：md5sum同样结果的.md5文件
 generate_file_md5sumFile(fpath)

[crazyant@localhost PythonMd5]$ python generateMd5file.py
311d384505e3622ccf85d88930e2b0a0
generate success, fpath:/home/crazyant/workbench/PythonMd5/sample_file.md5
[crazyant@localhost PythonMd5]$ md5sum -c sample_file.md5
sample_file: OK