help for the parse of encrypted excel

[Christian Ren]

I used xlrd library for the parse of excel before. But now, I
encounter a problem that the file has been encrypted for some security
reason. On the official website, i found "xlrd will not attempt to
decode password-protected (encrypted) files. " :((
And I also tried another library called pyExcelerator, Unfortunately,
it failed all the same.
Is there anybody can tell me what's the solution to the parse of
encrypted excel? Thanks in advance.
(PS: for the user experience reason, I don't hope to save this file as
another copy)