I found Org-mode ELPA released source code is old and does not include some
patches and updates.

For example, file `ob-clojure.el` I found org-mode source has the latest
source
code, but not in Org-mode ELPA package source code. The latest commit of
`ob-clojure.el` is about 3 monthes ago.

I installed both packages `org` and `org-plus-contrib` in ELPA repository.


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