Mark region as src code. If prefix used then create new org entry with the region marked as src.

(define-key org-mode-map (kbd "C-c C-b") '
  (lambda()(interactive)
    (let ((stars (make-string (org-current-level) ?*)))
      (insert 
       (format 
        "%s%s \n#+begin_src emacs-lisp\n%s#+end_src\n%s" 
        (if current-prefix-arg "#+end_src\n\n") stars (delete-and-extract-region (region-beginning) (region-end)) (if current-prefix-arg (concat "\n" stars " \n#+begin_src emacs-lisp")))))))

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My Emacs Files At GitHub