I'm developing an Emacs package
https://github.com/stardiviner/org-send-ebook .
I found Org-mode hex spaces in filename with "%20", So I reverse this with
function `(url-unhex-string (org-element-property :path
(org-element-context)))`. But this only works for English filename. If it
is Chinese filename. this will caused error.

Is there Org-mode built-in function which return the file path with out
hexing spaces '%20' ?
Or Does Emacs has functions can unhex '%20' correctly on Chinese?

Here is the test case:
org link:
[[file:Data/Books/%E6%80%8E%E6%A0%B7%E8%AF%BB%E4%B9%A6.mobi][怎样读书 (mobi)]]
And there is the result of `(org-element-property :path
(org-element-context))`:
"Data/Books/%E6%80%8E%E6%A0%B7%E8%AF%BB%E4%B9%A6.mobi"

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