python文件的md5加密方法

from hashlib import md5
def md5_file(name):
  m = md5()
  a_file = open(name, 'rb') #需要使用二进制格式读取文件内容
  m.update(a_file.read())
  a_file.close()
  return m.hexdigest()
if __main__ == '__init__':
  print md5_file('d:/test.txt')

#!/usr/bin/python
#encoding=utf-8
import io
import sys
import hashlib
import string
def printUsage():
  print ('''''Usage: [python] pymd5sum.py <filename>''')
def main():
  if(sys.argv.__len__()==2):
    #print(sys.argv[1])
    m = hashlib.md5()
    file = io.FileIO(sys.argv[1],'r')
    bytes = file.read(1024)
    while(bytes != b''):
      m.update(bytes)
      bytes = file.read(1024)
    file.close()
    #md5value = ""
    md5value = m.hexdigest()
    print(md5value+"\t"+sys.argv[1])
    #dest = io.FileIO(sys.argv[1]+".CHECKSUM.md5",'w')
    #dest.write(md5value)
    #dest.close()
  else:
    printUsage()
main()