Python实现md5

'''    md5sum in Pythonex:    import hashlib    m = hashlib.md5('stunnel-4.48.tar.gz')    m.digest()    print m.hexdigest()'''try:  from hashlib import md5        #Python2.5 or later versionexcept:  from md5 import md5            #Python2.4 or before versionimport sysimport urllibdef sumfile(fobj):  m = md5()  while True:    d = fobj.read()    if not d:      break    m.update(d)    del(d)  return m.hexdigest()def sumstr(str):  m = md5()  m.update(str)  return m.hexdigest()def md5sum(fname):       try:    f = urllib.urlopen(fname, 'rb')    #f = open(fname, 'rb')  except:    return False  ret = sumfile(f)  f.close()    return retres=md5sum('http://stunnel.cybermirror.org/stunnel-4.48.tar.gz')print res