For example, I have a package =ob-restclient= installed. I type ~<s~ then press =[Tab]= to expand.
#+begin_src | #+end_src I type ~rest~ at "|" position. But org-mode's =pcomplete= does not complete those added extra babel languages. (I use ~company-mode~'s ~company-capf~ for Org-mode's ~pcomplete~.) In other way: I press =[C-c C-v C-d]= to insert a babel src block, it has ~restclient~ as option.
